The US is deploying an aircraft carrier strike group and a bomber task force in the Middle East to send a "clear and unmistakable" message to Iran that any attack on American interests or its allies will be met with "unrelenting force", National Security Advisor John Bolton has warned.

Bolton said on Sunday the decision to deploy the USS Abraham Lincoln Carrier Strike Group and a bomber task force to the US Central Command region in the Middle East was in response to a number of "troubling and escalatory indications and warnings" from Iran.

The deployment of the strike group and bomber task force comes after US President Donald Trump last month refused to give waivers to countries like India from buying oil from Iran, in an attempt to reduce Iran's oil exports to zero.

After coming to power, Trump withdrew from the Iranian nuclear deal last year and has imposed stringent sanctions against what he describes as the "authoritarian" Iranian regime.

"In response to a number of troubling and escalatory indications and warnings, 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," Bolton said.

"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," he said in a statement.

The US is seeking to ramp up pressure on Iran to counter what the White House perceives to be a potential threat.

Last month, the US designated Iran's Revolutionary Guard a foreign terrorist organisation, the first time the designation has been applied to a government entity.

The designation categorises Iran's military alongside groups like ISIS, al Qaeda, Hezbollah and Hamas.

Iran's Supreme Leader Ayatollah Ali Khamenei, who controls the elite military force, called the designation a "vicious move" and a "mistake."

The Trump administration insists that it is not seeking to topple Iran's Islamist regime, but that it only seeks to push the government to stop supporting proxy militias and terrorist groups and otherwise change its behaviour.

Some of the administration's critics, however, fear that its actions and rhetoric could provoke the Iranians in a manner that may lead to a military confrontation.

Bolton's remarks also came as new violence erupts between Israel and the Palestinians in Gaza. The group Islamic Jihad, which has a foothold in Gaza, is seen as an Iranian proxy.

Trump recently tweeted about the violent situation in southern Israel and Gaza.

"We support Israel 100 per cent in its defense of its citizens," Trump said.

"To the Gazan people — these terrorist acts against Israel will bring you nothing but more misery. End the violence and work towards peace - it can happen!" he said.