A US Navy supercarrier anchored off the Israeli port of Haifa Saturday on a break from operations supporting the US-led coalition's fight against the Islamic State group.

It is the vessel's first visit to Israel in 17 years, according to the Israeli military.

An AFP photographer said that the USS George H.W. Bush dropped anchor around five kilometres (three miles) offshore.

Israeli public radio said it did not enter the port due to its 333 metre (1,000 foot) length.

"The carrier is a part of the coalition's effort against the Islamic State," the Israeli military said in a brief statement.

It said that in a joint excercise at sea earlier in the week an Israel Air Force helicopter landed on the vessel.

The massive, nuclear-powered Nimitz-class aircraft carrier has 4,800 personnel aboard, according to its Facebook page.

It rises 20 storeys above the waterline and typically carries around 80 warplanes.

Israeli radio said that it was expected to remain until Wednesday and that crew would celebrate 4th July onshore in Israel.

Other media reports said it was on its way to patrol off the Syrian coast and would be the first US carrier deployed there since April, when warships in the Mediterranean fired 59 Tomahawk missiles at the Syrian air force's Shayrat base.

The April strikes were ordered by US President Donald Trump in retaliation for what he said was a "barbaric" chemical attack by the Damascus regime on a rebel-held town in northwestern Syria.

On Monday the White House said that Syrian President Bashar al-Assad could be preparing "another mass murder attack using chemical weapons" and warned that the regime would pay a "heavy price" if it went ahead.

source: AFP