The United States is deploying a naval strike group to the Middle East in “response to a number of troubling and escalatory indications and warnings” from Iran, declared National Security Adviser John Bolton Sunday. “The United States is deploying the USS Abraham Lincoln Carrier Strike Group and a bomber task force to the US Central Command region to send a clear and unmistakable message to the Iranian regime that any attack on United States interests or on those of our allies will be met with unrelenting force,” he added. Bolton did not provide any further details. The move has been ordered “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,” said a US official on condition of anonymity. He added that the Washington was not expecting any imminent Iranian attack. Though Bolton cited no specific Iranian activities that have raised new concerns, Iran has recently warned it would block the Strait of Hormuz if it was barred from using the strategic waterway. About a fifth of the oil consumed globally passes through the strait. “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 Iranian Revolutionary Guard Corps or regular Iranian forces,” he said in a statement. A defense official tells The Associated Press that the Pentagon approved the deployments of the USS Abraham Lincoln and its strike group of ships and combat aircraft. It marked the latest in a series of moves by President Donald Trump’s administration aimed at ratcheting up pressure on Iran in recent months. 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 Revolutionary Guard, taking the unprecedented step of designating it as a foreign terrorist organization, which Iran has cast as an American provocation. 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. The threat late last month from the IRGC to close the Strait of Hormuz followed a US announcement that it would end exemptions granted last year to eight buyers of Iranian oil and demanding they stop purchases by May 1 or face sanctions. A senior Trump administration official said at the time that any aggressive move by Iran in the strait would be unjustified and unacceptable. Iran has made threats to block the waterway in the past, without acting on them.