Ahead of the meeting, Mogherini declined to answer a question about a speech by US Vice President Mike Pence on Thursday in which he accused the EU in general, and Germany, Britain and France in particular, of trying to undermine US sanctions on Iran over its nuclear program.
Pence's remarks at a Warsaw peace conference highlighted the differences between Washington and Brussels over the 2015 nuclear deal between Iran and world powers, from which the US under President Donald Trump withdrew last year.
Pompeo himself, who is also known as an outspoken critic of Iran, told reporters at the Warsaw conference that it was not possible to "achieve stability in the Middle East without confronting Iran."
Read more: Iran sanctions: 5 things to know
Call for EU withdrawalWashington claims Iran has been violating the terms of the 2015 deal, under which Tehran agreed to curb its nuclear program in exchange for the lifting of sanctions. In his speech on Thursday, Pence once more called on the EU to join the US in withdrawing from the deal.
Mogherini, speaking at a NATO meeting earlier the same day, reiterated the EU's view that upholding the deal was essential because it prevented Iran from developing a nuclear weapon.
In January, Germany, Britain and France agreed to evade US sanctions by opening a new channel for non-dollar trade with Iran. The so-called Special Purpose Vehicle (SPV), which is meant to help match Iranian oil and gas exports against purchases of EU goods, will, however, not become operational for months. Diplomats also say that the trade vehicle will be used only for trade on a small scale, for example in humanitarian goods or food.
European countries have, however, said that they, like Washington, are concerned about Iran's involvement in wars in Yemen and Syria. In practice, European countries have given up plans to invest in Iran in deference to the US sanctions.
tj/rt (Reuters, AP)
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