Russia will deliver another batch of 12 Sukhoi Su-30MK2 fighter aircraft under a recent contract worth about $450 million, a defense industry source told RIA Novosti on Wednesday.

The contract was reportedly signed last week, and the Su-30s are expected to be delivered to Vietnam in 2014-2015.

“A similar modification, priced at $35-37 million per plane, had been earlier sold to China,” the source said.

Russia has delivered a total of 20 Su-30 fighter jets under two previous contracts signed in 2009 and 2010.

Su-30MK2 is an advanced two-seat version of the Su-27 Flanker multirole fighter with upgraded electronics and capability to launch anti-ship missiles.

Combat aircraft remain the core of the Russian arms exports. Sukhoi Su-27/30 Flanker and Mikoyan MiG-29 Fulcrum fighter jets, Mil Mi-24/35 helicopter gunships, Mi-17 combat transport helicopters and Kamov Ka-28/31 naval helicopters are among the best-selling items in the aviation segment of arms exports.