Rishi Sunak will argue that Britain is safer under the Conservatives against the backdrop of two escalating conflicts likely to dominate the week.
In the last few days, the prime minister has broken with US President Joe Biden by insisting the UK should continue to supply arms to Israel.
It comes as Israeli PM Benjamin Netanyahu appears poised to mount another massive military operation in the southern Gaza town of Rafah against warnings from the US and UK.
Meanwhile, there are fears in Whitehall that Russia could mount an operation on Kharkiv by the end of the week to retake Ukraine‘s second-largest city.
Both operations could trigger wider repercussions.
Amid this worsening global outlook, the Conservatives want to highlight what they say is the gap between Tory and Labour pledges on military spending.
After the initial announcement, Sunak wants to ensure he gets full public credit for the big spending commitment while pushing Labour on its failure to match the promise.
Labour says that the Tory spending plan does not add up.
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Israel arms embargo ‘not a wise path’
On Monday, Sunak will use a set-piece speech to mount the argument that there is a need for security at home and abroad in an ever-increasingly dangerous world and describe the country as being at a crossroads at the next general election.
In a further major political dividing line, Labour has broken with the government and called this weekend for a suspension of arms to Israel, placing it alongside the United States.
However the Tory government is holding firm, arguing that now is not the time and that Britain only supplies a small amount of the munitions used by Israel.
Some people inside government suggest that the US government position is driven by President Biden’s need to take a tougher position to shore up votes in the upcoming election race.
Sunak’s Monday speech is one part of a set of security-themed announcements by the government, following Lord Cameron’s media blitz at the weekend.
On Monday, deputy foreign secretary Andrew Mitchell will address a Tory-leaning think tank, while on Tuesday Defence Secretary Grant Shapps will make a speech, with Chancellor Jeremy Hunt speaking on Friday.
Also, Deputy Prime Minister Oliver Dowden will lead a trade delegation this week to Saudi Arabia.
Although boosting trade will be the focus, Saudi Arabia, like Qatar, is one of the backchannels used by the UK to deliver messages to Hamas.
A woman has suffered life-changing injuries after being stabbed by a member of the public at the accident and emergency department where she was working.
The victim – believed to be a nurse in her 50s – was attacked at Royal Oldham Hospital in Greater Manchester, where she is now being treated.
It is understood she was injured with a bladed article or a sharp instrument – and not by a knife.
Officers were called at 11.30pm on Saturday.
A 37-year-old man is in custody after being “swiftly arrested at the scene” on suspicion of attempted murder, Greater Manchester Police said.
Detectives are not looking for anyone else in connection with the incident and say there is no threat to the wider public.
Jim McMahon, the Labour MP for the area, described it as a “senseless attack”.
He posted on Facebook: “We are all shocked at the senseless attack on a nurse in the A&E department of the Royal Oldham Hospital.
“Our thoughts are with the nurse, family and friends as we wish a full recovery.”
Detective Sergeant Craig Roters said it was a “serious incident which has left a woman in a critical condition”.
The victim’s family and colleagues will be supported, he added.
The local community can expect to see an “increase in police presence” while enquiries are carried out, Mr Roters said.
“We know that news of this nature will come as a shock, and if you have any concerns or anything you would like to share, please speak to [officers].”
Conservative Party leader Kemi Badenoch has called on Sir Keir Starmer to sack Treasury minister Tulip Siddiq over allegations she lived in properties linked to allies of her aunt, Sheikh Hasina, the deposed prime minister of Bangladesh.
It comes after the current Bangladeshi leader, Muhammad Yunus, said London properties used by Ms Siddiq should be investigated.
He told the Sunday Timesthe properties should be handed back to his government if they were acquired through “plain robbery”.
Tory leader Ms Badenoch said: “It’s time for Keir Starmer to sack Tulip Siddiq.
“He appointed his personal friend as anti-corruption minister and she is accused herself of corruption.
“Now the government of Bangladesh is raising serious concerns about her links to the regime of Sheikh Hasina.”
Ms Siddiq insists she has “done nothing wrong”.
Her aunt was ousted from office in August following an uprising against her 20-year leadership and fled to India.
On the same day, the prime minister said: “Tulip Siddiq has acted entirely properly by referring herself to the independent adviser, as she’s now done, and that’s why we brought into being the new code.
“It’s to allow ministers to ask the adviser to establish the facts, and yes, I’ve got confidence in her, and that’s the process that will now be happening.”
Police in Aberdeen have widened the search area for two sisters who disappeared four days ago in the city.
Eliza and Henrietta Huszti, both 32, were last seen on CCTV on Market Street after leaving their home on Tuesday at around 2.12am.
The sisters – who are part of a set of triplets and originally from Hungary – crossed the Victoria Bridge to the Torry area and turned right on to a footpath next to the River Dee.
They headed in the direction of Aberdeen Boat Club but officers said there is no evidence to suggest the missing women left the immediate area.
Specialist search teams, police dogs and a marine unit have been trying to trace the pair.
Further searches are being carried out towards the Port of Aberdeen’s South Harbour and Duthie Park.
Police Scotland said it is liaising with authorities in Hungary to support the relatives of the two sisters.
Chief Inspector Darren Bruce said: “Eliza and Henrietta’s family are understandably extremely worried about them and we are working tirelessly to find them.
“We are seriously concerned about them and have significant resources dedicated to the inquiry.”
The sisters, from Aberdeen city centre, are described as slim with long brown hair.
Officers have requested businesses in and around the South Esplanade and Menzies Road area to review their CCTV footage for the early morning of Tuesday 7 January.
Police added they are keen to hear from anyone with dashcam footage from that time.