The Sukhoi-27 plane crashed at around 5:00 pm local time (1400 GMT) "during a training flight", the army general staff said on its Facebook page, adding that "the bodies of the two pilots have been found".

The circumstances of the crash are being investigated, the statement said.

The general staff initially announced that an American pilot was among the dead but removed the information from their official Facebook page, according to the Interfax news agency.

Bogdan Senyk, a spokesman for the general staff, told AFP that the earlier message was "likely erroneous information", when asked about the change.

The crash occurred in the Vinnytsia region, around 180 kilometres (110 miles) southwest of Kiev.

Senyk said the two-seater jet was flying as part of large-scale air force exercises called Clear Sky 2018 involving the United States and other NATO countries, which began on October 8.

"This kind of flight is done by very experienced pilots," he added.

The exercises run until Friday.

They involve US fighter and transport planes training with about 30 Ukrainian aircraft.

Some 700 troops are taking part, half of them from NATO member countries including the United States, Britain, the Netherlands, Poland and Romania.

The aim is "to enhance regional capabilities to secure air sovereignty and promote peace and security through cooperation," a US Air Force statement said as the drills kicked off last week.

In recent years, concerns have risen about Russia's intentions in Ukraine, particularly after Moscow's annexation of the Crimean peninsula in 2014.

Kiev, which is not a member but wants to join NATO, and the West have accused Russia of backing rebels in Ukraine's war-torn east and sending troops across the border, claims Moscow has repeatedly denied.

The conflict has claimed more than 10,000 lives since April 2014.

bur-am/klm/bmm

Facebook