The Greek government will open talks on buying some 420 armored vehicles from Russia.
A Defense Ministry official said senior Cabinet officials approved the start of "substantive negotiations" on the purchase, which would include talks on possible joint production of the medium-sized tanks.
The official could not say how much the deal would be worth. He was speaking on customary condition of anonymity.
State NET television said some 1.2 billion EUR(US$1.8 billion) had been budgeted for the military vehicles.
Greek Prime Minister Costas Karamanlis is expected to pay an official visit to Russia on Dec. 17-19.
The government also decided to send up to 12 more military instructors to Afghanistan, where 170 Greek troops are stationed.
More than 3,500 people were detained during unprecedented mass protests that swept across all of Russia in support of Alexey Navalny on January 23