The shadow foreign secretary lost her cool with Foreign Office Minister Tobias Ellwood on Sky News’ All Out Politics after he hailed Britain’s standing with the US leader.
But the Labour frontbencher launched at her Tory counterpart and said the UK was “losing credibility”.
She said: “I fear that the Conservatives’ attitude to foreign policy is now ‘we’re waiting for Donald Trump to tell us what our foreign policy ought to be’.
“Otherwise, why are you not putting any other countries into your manifesto?”
Emily Thornberry blasted Tobias Ellwood over Theresa May's relationship with Donald Trump
We are not Donald trump’s mini me, we ought to have our own standing!
After the interruption during the heated exchange, Mr Ellwood continued to defend Mrs May building links with the billionaire tycoon.
“Can I finish?” he continued. “We should recognise that after Brexit has taken place we have to work out what our role is on the international stage.
“We have a reach and an influence which is second to none across the world, not just with the United States but with Europe as well.
“We are seen as the world’s leading soft power because we’re trusted, we are committed and we are knowledgeable about what is happening around the world.”
President Donald Trump makes historic visit to Israel Mon, May 22, 2017
President Trump and his contingent arrived for a 28-hour visit to Israel and the Palestinian Authority areas on his first foreign trip since taking office in January
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US President Donald Trump visits the Western Wall, the holiest site where Jews can pray, in Jerusalems Old City on May 22, 2017
Emily Thornberry and Tobias Ellwood during the heated debate
But Ms Thornberry cut in once more and suggested the UK was becoming a “mini me” to President Trump.
She said: “We are losing credibility because of our attitude to Donald Trump, we are being laughed at by other countries because we are so obsequious.
“We are not Donald trump’s mini-me, we ought to have our own standing.”
Mr Ellwood then accused Labour of wanting to “back away from our closest ally” after his Labour rival called on Mrs May to “tell truth to power”.
The Tory politician insisted it was now more important than ever to “show leadership” and said the Government had already done so in Somalia, Syria and South Sudan.
He said: “At a point where, yes there are many countries around the world, not just America that are becoming more insular and dangerous and changing, it is important that Britain steps up and shows that leadership.”