The US has sent four of its F-22 stealth fighter jets to South Korea as a warning to the North after its latest rocket launch.
The radar-evading Raptor jets, accompanied by eight more planes from South Korea and the US, flew to Osan Air Base near Pyeongtaek, 45 miles (70km) south from the border with North Korea.
Lieutenant General Terrence J O’Shaughnessy, commander of US 7th Air Force, said the mission demonstrated the strength of the US’ alliance with South Korea and “the resolve of both nations to maintain stability on the Korean Peninsula.”
He added that the US has an “ironclad commitment” to the defence of South Korea.
The jets, the most advanced in the US Air Force, are normally based on Japan’s Okinawa Island.
The move comes after North Korea said it sent a satellite into space, the latest in a series of rocket and nuclear tests which have prompted UN condemnation.
On Tuesday, the South Korean president Park Geun-hye promised “strong measures” if North Korea continued to test its nuclear capabilities.
Last month, the US flew its B-52 bombers over the country, after North Korea apparently carried out its fourth nuclear test.
The US did not say how long the Raptor jets would be stationed in South Korea.
Talks are due to start this week between Seoul and Washington, which would see the American missile defence system, the Terminal High Altitude Area Defence System (THAAD), deployed in South Korea.