TOKYO — Japan’s incoming Prime Minister Yukio Hatoyama reassured U.S. leaders Thursday that their security alliance remains the foundation of its foreign policy, despite pre-election promises that Tokyo would seek a more independent path.Hatoyama’s Democratic Party of Japan, meanwhile, neared an agreement with two smaller parties Thursday on launching a coalition to push aside the outgoing Liberal Democratic Party, rein in the national bureaucracy, and set a new course for the world’s second-largest economy.The party won 308 of the 480 seats in the powerful lower house of parliament in Sunday’s elections. The landslide victory ended decades of rule by the Liberal Democrats.Hatoyama, to be installed as premier Sept. 16, spoke with President Barack Obama by telephone early Thursday and then paid a visit to Washington’s new ambassador to Japan for his first discussions with any diplomats here.Hatoyama assured Obama the U.S.-Japan security alliance remains the “foundation” of Japan’s foreign policy.“The talks were cordial,” Hatoyama told reporters Thursday. “I think we will have good relations.”During the election campaign, Hatoyama said he would end Japan’s refueling operations in the Indian Ocean in support of U.S. troops in Afghanistan, and questioned plans to relocate a U.S. Marine air station on the southern island of Okinawa.He later toned down his rhetoric, insisting the U.S.-Japan alliance is vital to Tokyo’s foreign relations — a point he stressed in his phone call with Obama and his meeting with Ambassador John Roos.Under pressure from coalition partners such as the Social Democratic Party, which is expected to be a part of Hatoyama’s yet-to-be-named Cabinet, he has said he will let the refueling mission end when its mandate finishes in January.The Obama government has worked to boost relations with Japan after they cooled somewhat under the previous administration. U.S. officials have been quick to embrace the incoming government.Roos, who met with Hatoyama for about 40 minutes, called the meeting “very warm” and said they discussed the “very deep relationship” between the countries.“We spent a lot of time talking about how to enhance and further deepen that relationship across a broad range of issues,” Roos said in a statement.