IRAN held annual military drills with Russia on Thursday as a second United States aircraft carrier drew closer to the Middle East.

This comes as both the US and Iran are signalling they are prepared for war if talks on Tehran’s nuclear programme fizzle out.

US President Donald Trump said Thursday he believes that 10 to 15 days is “enough time” for Iran to reach a deal. 

But the talks have remained deadlocked for years and have been accompanied by crippling sanctions against Iran by the West.

In a letter to the United Nations security council on Thursday, Amir Saeid Iravani, the Iranian ambassador to the world body, said that while Iran does not seek “tension or war and will not initiate a war,” any US aggression will be responded to “decisively and proportionately.”

“In such circumstances, all bases, facilities, and assets of the hostile force in the region would constitute legitimate targets in the context of Iran’s defensive response,” Mr Iravani said.

Earlier this week, Iran conducted a drill that involved live-fire in the Strait of Hormuz, the narrow opening of the Persian Gulf through which a fifth of the world’s traded oil passes.

The movements of additional US warships and airplanes, with the USS Gerald R. Ford aircraft carrier near the mouth of the Mediterranean Sea bolster President Trump’s ability to carry out one should he choose to do so.

On Thursday, the US President said: “It’s proven to be, over the years, not easy to make a meaningful deal with Iran, and we have to make a meaningful deal. Otherwise, bad things happen.” 

One senior regional government official said he has stressed to Iranian officials in private conversations that President Trump has proven that his rhetoric should be taken at face value and that he’s serious about his threat to carry out a strike if Iran doesn’t offer adequate concessions.