The Oakland-Alameda County Coliseum Authority, a joint-powers authority that is a partnership between the city of Oakland and Alameda County, voted 7-1 to approve both leases, with sports agent Aaron Goodwin casting the lone "no" vote on both matters.
The lease for the A's, which had been scheduled to expire at the end of this year, was extended for two years, through Dec. 31, 2015.
The lease for the Raiders, which also had been set to expire at the end of the year, was extended for just one year, through the end of the 2014-15 football season.
JPA officials said the Raiders will pay $400,000 for the one-year extension, and the A's will pay the authority $1.75 million a year.
Oakland City Councilman Larry Reid, who serves as the board's vice chair, said city and county officials would have liked to reach longer-term agreements with both teams but that the teams only want short-term leases at this time.
Even though the leases for the two teams are short, Reid said, "I am very hopeful both will stay in Oakland" for the long term.
Reid said the city and county have a good relationship with the Raiders but that the football team doesn't want to commit to staying in Oakland until more progress is made on building a new stadium for them. He said the team wants to be in a new stadium by 2017.
Oakland A's owner Lew Wolff is still seeking to move the baseball team to San Jose, but Reid noted that Major League Baseball is still blocking that move and said Oakland is working on plans to build a new baseball-only stadium for the team.