Iranian Foreign Minister Javad Zarif has condemned the US for promising to impose the "strongest sanctions in history" on his country. Measures outlined by US Secretary of State Mike Pompeo, he said, showed the US was a prisoner of its "failed policies" and it would suffer the consequences, BBC reported on Monday. EU foreign policy chief Federica Mogherini also criticised the US. She said Pompeo had failed to show how dropping the 2015 nuclear deal would make the Middle East safer. There was, she said, "no alternative" to the agreement, which US President Donald Trump vowed earlier this month to abandon, and she said the EU would stick by it if Iran met its commitments. Despite the EU's official position, some of Europe's biggest firms who rushed to do business with Iran after the nuclear deal now find themselves forced to choose between investing there or trading with the US. US sanctions lifted after the 2015 deal would be re-imposed, he said, and those and new measures would together constitute "unprecedented financial pressure on the Iranian regime". He set out conditions for any new deal with Iran, including the withdrawal of its forces from Syria and an end to its support for rebels in Yemen. The older US sanctions prohibited almost all trade with Iran. Pompeo did not say what new measures Washington was contemplating but described sanctions imposed last week on the head of Iran's central bank as "just the beginning". Iran is one of the world's largest oil producers, and the export of oil and gas is worth billions of dollars each year. Both the country's oil output and its GDP fell noticeably under international sanctions. The sanctions will not be re-imposed on Tehran immediately but are subject to three-month and six-month wind-down periods. Zarif said America was "regressing to old habits" but his country was working with other partners to the nuclear deal in order to find a solution. Iranian President Hassan Rouhani launched a personal attack on Mike Pompeo, questioning his credibility as a former CIA chief to make decisions for Iran and the world.