Jens Stoltenberg

Turkey's military, meanwhile, said more of its jets patrolling the border with Syria were placed in a radar lock by Russian planes and surface-to-air missile systems.

In Syria, Russian warplanes reportedly continued pounding targets in the country, where the Kremlin has come to the aid of beleaguered ally President Bashar Assad.

NATO Secretary-General Jens Stoltenberg, who joined Lithuanian President Dalia Grybauskaite for the opening ceremony, described the new unit as a "big step forward toward greater solidarity, greater strength and greater readiness."

The NATO force integration unit in Vilnius is one of six small headquarters — manned by some 40 staff each — that opened this month in Bulgaria, Estonia, Latvia, Poland and Romania, as part of the alliance's biggest reinforcement of collective defense since the end of the Cold War.

NATO Secretary-General Jens Stoltenberg said the aid program, approved Friday by NATO member nations, is designed to help Iraq by providing support in areas where NATO "is best placed to add value."

Stoltenberg said the assistance program was developed at Iraq's request, and in close consultation with Iraqi authorities.

Stoltenberg called Greece "a staunch ally and a committed ally" on Thursday. He said the Greek government stands by its "commitments in the alliance. This good for Greece and good for NATO."