LONDON -- British Prime Minister Keir Starmer said on Wednesday that the United Kingdom will "not yield" to external pressure to join the ongoing conflict involving Iran, highlighting a widening divergence with the United States over both security and economic issues.

Speaking during Prime Minister's Questions in parliament, Starmer made clear that Britain would not alter its position despite mounting pressure.

"It is not our war and a lot of pressure has been applied to me to take a different course, and that pressure included what happened last night. I'm not going to change my mind," he said.

His remarks came after US President Donald Trump, in an interview with Sky News on Tuesday night, sharply criticized Britain's stance and signaled a more confrontational tone toward bilateral ties.

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Trump suggested that the UK had failed to support the United States at a critical moment in its military campaign, saying: "When we needed them, they were not there. When we didn't need them, they were not there. And they still aren't there."

He described the long-standing US-UK "special relationship" as strained, saying it had "been better" and was now "sad".

Trump also linked security differences to economic relations, warning that Washington could revisit last year's trade agreement and offer the UK less favorable terms.

In response, Starmer reiterated that the British government would prioritize national interest and maintain policy independence in both foreign and economic affairs.

"The UK is not going to get dragged into this war," he said. "I'm not going to yield. It is not in our national interest to join this war and we will not do so."