Sir Keir Starmer has said the government has been preparing “for all eventualities” ahead of Donald Trump announcing global tariffs later on Wednesday.
The US president is set to announce details of fresh tariffs on imports into the US after he said all countries will be targeted in his bid to “rebalance” trade agreements.
Mr Trump is expected to announce 20% tariffs on most US imports on what he has called “Liberation Day”.
However, he admitted it is likely “there will be tariffs” as negotiators had not managed to fend them off in time.
At PMQs, Sir Keir rejected jumping into a trade war with the US, saying: “That cannot be the first response of the United Kingdom.”
The impact of potential retaliatory tariffs from the EU on Northern Ireland was also raised, with DUP MP Gavin Robinson reminding the prime minister not to forget the unique trade situation in Northern Ireland.
He said while exports from Northern Ireland are UK exports, imports to the country could be hit by tariffs imposed by the EU as it shares a border with the European bloc.
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PM holding fire on Trump’s Liberation Day tariffs
The Belfast East MP asked whether government trade teams are attempting to exempt Northern Ireland from any EU action.
Sir Keir reacted by saying what is needed is to be “calm and pragmatic”.
He added the business secretary had spoken to the Northern Ireland government on Wednesday morning, “because this is a serious issue and we need to work together to resolve the interests of everybody in Northern Ireland”.
Last week, Mr Trump said he was open to carving out deals with countries seeking to avoid US tariffs, but those agreements would be negotiated after 2 April.
He previously said he “may give a lot of countries breaks, but it’s reciprocal”, adding: “We might be even nicer than that.”