Chip giant Nvidia pushed back Sunday in response to allegations from Chinese state media that its H20 artificial intelligence chips are a national security risk for China.

Earlier in the day, Reuters reported Yuyuan Tantian, an account affiliated with Chinese state broadcaster CCTV, said in an article published on WeChat that the Nvidia H20 chips are not technologically advanced or environmentally friendly.

“When a type of chip is neither environmentally friendly, nor advanced, nor safe, as consumers, we certainly have the option not to buy it,” the Yuyuan Tantian article reportedly said, adding that the article said chips could achieve functions including “remote shutdown” through a hardware “backdoor.”

In response, a Nvidia spokesperson told CNBC that “cybersecurity is critically important to us. NVIDIA does not have ‘backdoors’ in our chips that would give anyone a remote way to access or control them.”

Nvidia on Tuesday similarly rejected Chinese accusations that its AI chips include a hardware function that could remotely deactivate the chips, also known as a “kill switch.”

Tensions between the U.S. and China on semiconductor export controls have escalated in recent weeks, even after Nvidia resumed sales of its H20 chip to China. Chinese state media has framed the H20 chip as inferior and dangerous compared to Nvidia’s other chips, while the company has defended its chips.

The company’s resumption of its H20 shipments reversed a previous ban on H20 sales that was placed in April by the Trump administration. Nvidia’s H20 chips — a less-advanced semiconductor compared to its flagship H100 and B100 chips, for example — were developed by Nvidia for the Chinese market after initial export restrictions on advanced AI chips in late 2023.

U.S. export controls on some Nvidia chips are rooted in national security concerns that Beijing could use the more advanced chips to gain an advantage broadly in AI, as well as in its military applications.

Chinese officials, meanwhile, are pushing for the U.S. to ease export controls on high-bandwidth memory chips as part of a trade deal before a possible summit between U.S. President Donald Trump and Chinese President Xi Jinping, the Financial Times reported on Sunday, citing people familiar with the matter.

Nvidia CEO Jensen Huang has supported Trump’s policies while also lobbying for export licenses for the H20 AI chip. Huang has said he wants Nvidia to ship more advanced chips to China, underscoring his outspoken stance that Nvidia’s chips becoming the global standard for AI computing is ultimately better for the U.S. to retain market dominance and influence over global AI development.

China is among Nvidia’s largest markets. Nvidia took a $4.5 billion writedown on its unsold H20 inventory in May and has warned that its topline guidance for the July quarter would have been higher by $8 billion without the chip export restrictions.

Nvidia shares were up 1% to close at $182.70 on Friday and are up 36% this year.

Apple shares rose 13% this week, its largest weekly gain in more than five years, after CEO Tim Cook appeared with President Donald Trump in the White House on Wednesday.

Shares of the iPhone maker rose 4% to close at $229.35 per share on Friday for the company’s largest weekly gain since July 2020. The week’s move added over $400 billion to Apple’s market cap, which now sits at $3.4 trillion.

Apple is the third-most valuable company, behind Nvidia and Microsoft and ahead of Alphabet and Amazon.

At the White House on Wednesday, Cook appeared with Trump to announce Apple’s plans to spend $100 billion on American companies and American parts over the next four years.

Apple’s plans to buy more American chips pleased Trump, who said during the public meeting that because the company was building in the U.S., it would be exempt from future tariffs that could double the price of imported chips.

Investors had worried that some of Trump’s tariffs could substantially hurt Apple’s profitability. Apple warned in July that it expected over $1 billion in tariff costs in the current quarter, assuming no changes.

“Apple and Tim Cook delivered a masterclass in managing uncertainty after months and months of overhang relative to the potential challenges the company could face from tariffs,” JP Morgan analyst Samik Chatterjee wrote on Wednesday. He has an overweight rating on Apple’s stock.

Cook’s successful White House meeting also comes two weeks after Apple reported June quarter earnings in which overall revenue jumped 10% and iPhone sales grew by 13%.

WATCH: Santoli’s Last Word: Apple helps drive S&P higher

Tesla has been granted a permit to run a ride-hailing business in Texas, allowing the electric vehicle maker to compete against companies including Uber and Lyft.

Tesla Robotaxi LLC is licensed to operate a “transportation network company” until August 6, 2026, according to a listing on the website of the Texas Department of Licensing and Regulation, or TDLR. The permit was issued this week.

Elon Musk’s EV company has been running a limited ride-hailing service for invited riders in Austin since late June. The select few passengers have mostly been social media influencers and analysts, including many who generate income by posting Tesla fan content on platforms like X and YouTube.

The Austin fleet consists of Model Y vehicles equipped with Tesla’s latest partially automated driving systems. The company has been operating the cars with a valet, or human safety supervisor in the front passenger seat tasked with intervening if there are issues with the ride. The vehicles are also remotely supervised by employees in an operations center.

Musk, who has characterized himself as “pathologically optimistic,” said on Tesla’s earnings call last month that he believes Tesla could serve half of the U.S. population by the end of 2025 with autonomous ride-hailing services.

The Texas permit is the first to enable Tesla to run a “transportation network company.” TDLR said Friday that this kind of permit lets Tesla operate a ride-hailing business anywhere in the state, including with “automated motor vehicles,” and doesn’t require Tesla to keep a human safety driver or valet on board.

Tesla didn’t immediately respond to a request for comment.

As CNBC previously reported, Tesla robotaxis were captured on camera disobeying traffic rules in and around Austin after the company started its pilot program. None of the known incidents have been reported as causing injury or serious property damage, though they have drawn federal scrutiny.

In one incident, Tesla content creator Joe Tegtmeyer reported that his robotaxi failed to stop for a train crossing signal and lowering gate-arm, requiring a Tesla employee on board to intervene. The National Highway Traffic Safety Administration has discussed this incident with Tesla, a spokesperson for the regulator told CNBC by email.

Texas has historically been more permissive of autonomous vehicle testing and operations on public roads than have other states.

A new law signed by Texas Republican Gov. Greg Abbott goes into effect this year that will require AV makers to get approval from the state before starting driverless operations. The new law also gives the Texas Department of Motor Vehicles the authority to revoke permits if AV companies and their cars aren’t complying with safety standards.

Tesla’s AV efforts have faced a number of challenges across the country, including federal probes, product liability lawsuits and recalls following injurious or damaging collisions that occurred while drivers were using the company’s Autopilot and FSD (Full Self-Driving) systems.

A jury in a federal court in Miami last week determined that Tesla should hold 33% of the liability for a fatal Autopilot-involved collision.

And the California DMV has sued Tesla, accusing it of false advertising around its driver assistance systems. Tesla owners manuals say the Autopilot and FSD features in their cars are “hands on” systems that require a driver ready to steer or brake at any time. But Tesla and Musk have shared statements through the years saying that a Tesla can “drive itself.”

Since 2016, Musk has been promising that Tesla would soon be able to turn all of its existing EVs into fully autonomous vehicles with a simple, over-the-air software update. In 2019, he said the company would put 1 million robotaxis on the road by 2020, a claim that helped him raise $2 billion at the time from institutional investors.

Those promises never materialized and, in the robotaxi market, Tesla lags way behind competitors like Alphabet’s Waymo in the U.S. and Baidu’s Apollo Go in China.

Tesla shares are down 18% this year, by far the worst performance among tech’s megacaps.

WATCH: What we saw at Tesla’s robotaxi launch in Texas