TOKYO (AP) - Japan’s new ruling party will form a coalition government with two smaller groups, despite differences on foreign policy and the presence of U.S. Marines on Okinawa, party officials said Wednesday.

The agreement paves the way for Democratic Party of Japan leader Yukio Hatoyama to put together a new Cabinet. Hatoyama is almost certain to become Japan’s next prime minister in a parliament vote scheduled for Sept. 16.

The left-of-center Democrats won a sweeping victory in elections on Aug. 30 for the 480-seat lower house of parliament, giving them a simple majority. But they need the coalition with the smaller parties to control the less powerful upper house.

Hatoyama’s party will align with the Social Democratic Party and People’s New Party to replace the outgoing Liberal Democrats, a pro-big business and staunchly pro-U.S. party that had governed the country for more than 50 years.

Democratic Party of Japan spokesman Toshiaki Oikawa said the secretary-general of each party attended talks Wednesday at which they largely worked out their differences on defense issues and foreign policy.

The parties have disparate views on what to do about an agreement backed by the outgoing administration to close the U.S. Marine airfield in the crowded city of Futenma and find a new location for it elsewhere on the southern island of Okinawa - an issue that could complicate the new government’s relations with Washington.

The Democrats have opposed the current plan, with many in the party saying the replacement base should be moved off Okinawa or out of Japan altogether. The Social Democrats want the base moved out of Japan and want to re-examine the overall security alliance under which 50,000 U.S. troops are stationed in Japan. Washington has strongly opposed the idea of moving the airfield off Okinawa.

That issue and the question of whether - or how soon - Japan should end its refueling of U.S. ships in the Indian Ocean in support of the U.S.-led coalition in Afghanistan had stalled talks between the three parties, which have already coordinated their stances on measures to fight climate change, plans to freeze a tax hike planned by the outgoing Liberal Democrats and on a review of medical care for the elderly.

Oikawa declined to give details about how they reached a compromise.

Katsuya Okada, a Democratic Party leader who is expected to become foreign minister, said the parties wanted to get as close on policy issues as possible before taking over government next week.

"We want to have a good agreement, rather than a murky settlement, so that we can make a solid start," he said Wednesday.

Along with Okada, media reports have said 77-year-old veteran lawmaker Hirohisa Fujii is likely to be the finance minister, while Naoto Kan, the Democratic Party’s acting president, is to head a new agency in charge of setting government policies and strategies.

Social Democrat leader Mizuho Fukushima and People’s New Party chief Shizuka Kamei are also expected to get Cabinet positions.