WARSAW - U.S. Vice President Mike Pence said Iran advocates for 'another Holocaust' and accused Washington's European allies on Thursday of trying to break U.S. sanctions against Tehran, calleing on them to withdraw from the Iran nuclear deal.

"Sadly, some of our leading European partners have not been nearly as cooperative. In fact, they have led the effort to create mechanisms to break up our sanctions," Pence said during a conference on the Middle East organized by the United States in Warsaw.

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Pence said a scheme set up by the EU to facilitate trade with Iran was "an effort to break American sanctions against Iran's murderous revolutionary regime".

"It is an ill-advised step that will only strengthen Iran, weaken the EU and create still more distance between Europe and the United States," he said.

Earlier Thursday U.S. Secretary of State Mike Pompeo said it is impossible to achieve peace and stability in the Middle East without confronting Iran.

Speaking to reporters alongside Prime Minister Benjamin Netanyahu, Pompeo said "You can't achieve stability in the Middle East without confronting Iran. It's just not possible."

"There are malign influences in Lebanon, Yemen, Syria and Iraq," Pompeo added. "The three H's- the Houthis, Hamas and Hezbollah. These are real threats."

The Warsaw meeting was attended by more than 60 nations but major European powers such as Germany and France, part to the 2015 nuclear accord, refused to send their top diplomats.