US national security adviser says move is response to ‘a number of troubling and escalatory indications and warnings’.

The United States is deploying a carrier strike group and a bomber task force to the Middle East to send a clear message to Iran that any attack on US interests or its allies will be met with “unrelenting force”.

Amid rising tensions between Washington and Tehran, US National Security Advisor John Bolton said on Sunday that the deployment of the USS Abraham Lincoln Carrier Strike Group to the US Central Command region was a response “to a number of troubling and escalatory indications and warnings”.

“The United States is not seeking war with the Iranian regime, but we are fully prepared to respond to any attack, whether by proxy, the Islamic Revolutionary Guard Corps or regular Iranian forces,” Bolton said in a statement.

Al Jazeera’s Gabriel Elizondo, reporting from Washington, DC, said the move was an “unusual one” especially because of the statement by Bolton.

“There are more questions than answers in that short statement,” he said.

“It’s not unusual for aircraft carriers to be deployed to the Middle East to be a deterrent to Iran. But what makes this different is Bolton putting out a statement specifying Iran. It’s almost a provocation.

“That’s unusual for the US to do that when they deploy big military assets like these.”

Washington has said it will stop waivers for countries buying Iranian oil, in an attempt to reduce Iran’s oil exports to zero. It has also blacklisted Iran’s elite Revolutionary Guard Corps.

In response, Iran said it has mobilised all its resources to sell oil in a “grey market”.

Amir Hossein Zamaninia, Iran’s deputy oil minister, told state media on Sunday that Iran would continue to export oil despite the US sanctions, which he said were neither just nor legitimate.

“We have mobilised all of the country’s resources and are selling oil in the ‘grey market’,” state news agency IRNA quoted Zamaninia as saying.

“We certainly won’t sell 2.5 million barrels per day as under the [nuclear deal],” he said. “We will need to make serious decisions about our financial and economic management, and the government is working on that.”

The Trump administration’s efforts to impose political and economic isolation on Tehran began last year when it unilaterally withdrew from the nuclear deal it and other world powers negotiated with Iran in 2015.

Bolton, who has spearheaded an increasingly hawkish US policy on Iran, did not provide any other details.

A US official said the forces “have been ordered to the region as a deterrence to what has been seen as potential preparations by Iranian forces and its proxies that may indicate possible attacks on US forces in the region”.