The International Baseball Federation has formally approved a merger with softball's governing body in a joint bid to return to the Olympics.

IBAF says the creation of a single international federation received unanimous approval in a mail-in vote of its members.

The International Softball Federation approved the move in October.

IBAF President Riccardo Fraccari says "this is another critical step in the long-term prosperity and development of softball and baseball worldwide. We look forward to presenting an exceptional value proposal to the Olympic movement for 2020 and beyond."

Baseball and softball are bidding jointly to win a spot on the program for the 2020 Games.

The IOC will vote in September. Karate, roller sports, squash, sport climbing, wakeboard and wushu also are competing.

Baseball and softball, voted out by the IOC in 2005, were last played at the 2008 Beijing Olympics.