The US Navy is set to carry out a rare military exercise involving three aircraft carriers in the Western Pacific.

Timed to coincide with the last leg of Donald Trump's Asia tour, it will be the first time in a decade the USS Ronald Reagan, the USS Theodore Roosevelt and the USS Nimitz have operated together.

The display of military might comes amid heightened tensions in the region over North Korea's nuclear missile programme.

The operation will take place over the weekend and into early next week, the US Navy said in a statement. It is thought the drills will take place in the Sea of Japan, which borders the secretive communist state.

"It is a rare opportunity to train with two aircraft carriers together, and even rarer to be able to train with three," said US Pacific Fleet Commander Admiral Scott Swift.

"Multiple carrier strike force operations are very complex, and this exercise in the Western Pacific is a strong testament to the US Pacific Fleet's unique ability and ironclad commitment to the continued security and stability of the region."

The strike force plans to conduct air defence drills and defensive air combat training, the navy said.

It is the first time that three carrier strike groups have operated together in the Western Pacific since exercises in 2006 and 2007 off the coast of Guam.

Earlier this week, Mr Trump issued a stern warning to North Korea, repeating his vow that the US will defend itself and its allies against Pyongyang's nuclear aggression.

He directly addressed the North Korean leader Kim Jong-un, telling him “the weapons you are acquiring are not making you safer, they are putting your regime in grave danger”.

Mr Trump is currently in China on 12-day tour of five Asian countries. Earlier this week he was forced to scrap a surprise visit to the Demilitarised Zone (DMZ) between North and South Korea because of bad weather.