U.S. President Donald Trump said on Tuesday a lot of progress had been made with Iran and that he was not looking for regime change in Iran.

Britain will send a third warship to the Persian Gulf, though the move is not related to the current Iran crisis, the Ministry of Defence (MoD) said on Tuesday.

The United Nations told the United States it is concerned by tight travel restrictions on Iranian Foreign Minister Mohammad Javad Zarif during his visit to New York this week, U.N. spokesman Farhan Haq said on Monday.

Gibraltar police said on Friday that all four crew members of the Iranian Grace 1 tanker have been released on bail without charge after it was detained last week on suspicion of breaking European sanctions by taking oil to Syria.

The United States has decided not to impose sanctions on Iranian Foreign Minister Mohammad Javad Zarif for now, two sources familiar with the matter said on Thursday, in a sign Washington may be holding a door open for diplomacy.

Britain does not intend to escort every British-flagged merchant vessel through the Strait of Hormuz, a security source said on Thursday, after a Royal Navy warship had to stop three Iranian vessels from blocking the passage of a BP-operated tanker.

Gibraltar police said they have arrested the captain and chief officer of the detained Iranian Grace 1 supertanker accused of violating EU sanctions on Syria and have seized documents and electronic devices from the vessel.

French President Emmanuel Macron's top diplomatic advisor met with Iran's president Wednesday winding up a day of talks in Tehran aimed at saving a landmark 2015 nuclear deal and easing tensions between Tehran and Washington.

French President Emmanuel Macron's top diplomatic advisor will travel to Iran on Tuesday and Wednesday to try to de-escalate tensions between Tehran and the United States, a presidential official said on Monday.

Iran has enriched uranium beyond a 3.67% purity limit set by its deal with major powers, the U.N. nuclear watchdog policing the deal said on Monday, confirming a move previously announced by Tehran.

Iran threatened on Monday to restart deactivated centrifuges and ramp up enrichment of uranium to 20% purity in a move away from the 2015 nuclear deal, but the head of Iran's Revolutionary Guards insisted the world knows Tehran is not pursuing nuclear arms.

The UN's nuclear watchdog said Friday it will hold a special meeting on Iran's nuclear programme next week, days after Tehran breached one of the limits set in a 2015 deal with world powers.

U.S. President Donald Trump warned Iran Wednesday its threats could "come back to bite" after Tehran vowed to exceed the maximum uranium enrichment level allowed by a landmark 2015 nuclear accord.

The diplomatic chiefs of the EU, France, Germany and Britain said Tuesday they were "extremely concerned" and urged Iran to reverse its decision to breach a limit on enriched uranium reserves under a 2015 nuclear deal.

Britain, France and Germany will not for the moment trigger a dispute resolution mechanism enshrined in the 2015 Iran nuclear accord that could lead to the reimposition of United Nations sanctions, two European diplomats said.

Iran's foreign minister said on Twitter on Thursday that U.S. President Donald Trump's view that a conflict with Iran would be a "short war" was an illusion and that his threat of "obliteration" amounted to threatening "genocide".

U.S. President Donald Trump on Wednesday said he was "fine" if there was no new agreement with Iran, adding that he had "unlimited time" to try and reach a deal with Tehran.

U.S. Secretary of State Mike Pompeo said in an interview with local media in India on Wednesday that the United States had done everything it could to de-escalate tensions with Iran.

Iran will speed up enrichment of uranium after a deadline given to European countries to prevent this ends on Thursday, the spokesman for Iran's Atomic Energy Organization said on Wednesday, according to the IRIB news agency.

Iran said Tuesday new US sanctions against its leaders marked the end of diplomacy with Washington, after President Donald Trump threatened the country with "obliteration".