As AUTOSPORT revealed in February, former champion team iSport was on the verge of selling its GP2 entry to avoid potentially going bust later in the season.
Russian Time, nominally a Russian entry but based in Germany, has now been confirmed as the 13th entrant for this year's championship in place of iSport.
The team will join GP2's second pre-season test at Barcelona which starts tomorrow (March 5) and runs for three days.
GP2 boss Bruno Michel said he is confident Russian Time can be competitive despite the late entry into the championship.
"I am pleased to welcome Russian Time to GP2," he said. "I am certain that they will be a great addition to our field.
"Igor Mazepa has already put in place a team of staff with some great GP2 experience which will help them be able to be on pace very quickly.
"I would like to take this opportunity to thank iSport International and Paul Jackson for eight great seasons in GP2 and wish them all the best for the future."
Igor Mazepa, Russian Time team principal, added: "We're very happy to be joining the GP2 Series.
"It is one of the most prestigious categories in motorsport and we cannot wait to start running with the car this week in Barcelona.
"We know that it will be a challenge to be quickly on par with the other teams, but we have managed to put together a group of people whose experience in GP2 will be invaluable and we are pretty confident that we will do a good job from the get-go.
"We're looking forward to this first season and hope to add many more to it."
Russian Time is yet to announce its drivers for the upcoming season.