WASHINGTON - US Secretary of State Mike Pompeo said Washington still wants to work with its European partners on an agreement to counter Iran's "malign behavior" Sunday despite its withdrawal from a landmark nuclear deal.

President Donald Trump's announcement last Tuesday that the US was exiting the 2015 nuclear accord was met with widespread dismay in Europe where companies now face the threat of sanctions if they do business with Iran. But Pompeo said Washington was keen to thrash out a more wide-ranging deal with its allies as another top official said Iran had been "on the march" throughout the Middle East since the nuclear agreement was signed.

Pompeo, who is barely a fortnight into his new job, told Fox News Sunday that he had been tasked by the president "to work to strike a deal that achieves the outcomes that protect America."

"That's what we are going to do and I will be hard at it with the Europeans in the next several days," said the top US diplomat. "I'm hopeful in the days and weeks ahead we can come up with a deal that really works, that really protects the world from Iranian bad behavior, not just their nuclear program, but their missiles and their malign behavior as well. And I will work closely with the Europeans to try and achieve that." The administration says the lifting of sanctions as part of the nuclear pact had allowed Iran to build up its military, with Trump claiming on Saturday that Tehran's defense spending had risen by 40 percent since 2015.

John Bolton, who is Trump's national security advisor, said that Tehran's military had exploited the easing of pressure on the Iranian economy to meddle in conflicts across the Middle East in the last three years.  "If you look at the advances that Iran has made under cover of this agreement, its conventional military and terrorist advances, in Iraq, in Syria, in Lebanon, in Yemen, since 2015, Iran was really on the march," Bolton told ABC's "This Week." "They were shifting the balance of power in the Middle East until President Trump got out of this deal." Asked if Washington was now advocating for regime change in Iran, Bolton responded that it was not administration policy.

"The policy of the administration is to make sure that Iran never gets close to deliverable nuclear weapons," he added.

While he has committed to remaining in the nuclear agreement, French President Emmanuel Macron floated the idea of a supplemental deal on Iran during a recent visit to Washington. German leader Angela Merkel also told Trump on a visit to Washington late last month that the nuclear deal was insufficient in itself to curb Iran's ambitions in the region.

Germany, France and Britain were three of the six signatories to the 2015 pact which saw sanctions lifted in return for the commitment by Tehran not to acquire nuclear weapons.

Although most analysts believe the US withdrawal has effectively scuppered the agreement, Iran's foreign minister talked up the prospects of its survival on Sunday while visiting China, another of the signatories. "We hope that with this visit to China and other countries we will be able to construct a clear future design for the comprehensive agreement," Mohammad Javad Zarif told reporters after talks in Beijing with his Chinese counterpart Wang Yi.