The league has five days to approve or reject the deal, which media reports say amounts to $100 million over 15 years. A month ago, the NHL rejected a 17-year, $102 million contract for Kovalchuk, saying it violated the league salary cap.
After the rejection, the NHL Players Association filed a grievance and the league's decision was upheld by an arbiter.
The 27-year-old Russian left wing has 338 goals and 304 assists in 642 career games. He had 41 goals and 44 assists last season. New Jersey traded him to Atlanta in February.