San Francisco ? Baseball officials are moving ahead with plans to play regular-season games in Tokyo in 2008.

The Boston Red Sox, New York Yankees, Oakland Athletics and Seattle Mariners are American League teams interested in playing in Japan next year, several officials have said in recent weeks. The Los Angeles Dodgers, Pittsburgh Pirates and San Diego Padres have expressed interest among National League teams.

“I expect that we will have games in Tokyo next spring,” Bob DuPuy, baseball’s chief operating officer, said Tuesday before the All-Star game. “We’re looking at the schedule, looking at what’s available, looking at permutations, looking at teams training in Arizona vs. teams training in Florida.”

The Chicago Cubs and the New York Mets opened the 2000 season with a two-game series at the Tokyo Dome, and the New York Yankees and Tampa Bay Devil Rays started the 2004 season with two games there. A 2003 series between Seattle and Oakland at the Tokyo Dome was called off because of the threat of war in Iraq.

The players’ union agreed to postpone the deadline for a draft of the 2008 schedule from the end of June to the end of July.

Baseball also is interested in playing exhibition games in Beijing next spring, but planning for that appears to be going more slowly.

“We’re still batting around some ideas and frankly expect to have a position paper on the commissioner’s desk on or around the owners’ meetings in August,” DuPuy said.

Owners are next scheduled to meet Aug. 14-15 in Toronto.