Sofia has offered to donate its MiG-29s to Kiev, according to highly classified Pentagon documents leaked online in recent weeks, CNN reports.

On February 23, the report says, Bulgaria expressed willingness to donate its fleet of MiG-29 jets to Ukraine - a "challenge," the report assesses, because it will leave Bulgaria without fighter aircraft to fulfill its air policing missions until US-made F-16s are delivered, "which is at least a year away."

Of the 18 Bulgarian MiG-29 aircraft, no more than 8 are actually flying. If no engines are found for the obsolescent MiG-29s, their service life could be extended until at most the end of 2023, Defence Minister Dimitar Stoyanov admits. There is still no official response from the ministry to the information in the report, BTA reports.