A Reagan administration trade official told Japanese political and business leaders yesterday that Japan should set specific targets for "vastly increasing" its imports of manufactured goods to forestall worsening trade frictions with the United States.

Coincidentally with a speech in Tokyo by the official, Commerce Undersecretary Lionel Olmer, Japan estimated it had a record trade surplus of $29.06 billion for the first 11 months of 1984, compared with a $20.53 billion surplus for all of 1983.

Olmer pointed to the United States' growing trade deficit with Japan -- expected to reach $35 billion this year -- and said increasing imports should get "a national priority at least equivalent" to Japan's export goals, to forestall a growing feeling in the world that Tokyo does not play fair with its trading partners.

"Patience is running out because our access to the Japanese market is seen by almost everyone in my country and elsewhere as nowhere equal to Japan's access to other markets," Olmer said in a speech to the Research Institute of Japan, a well-regarded organization of Japanese political and business leaders.

"We are at a point," he continued, "where future economic problems threaten to more than offset the progress we have made to date."

His speech echoed a chord struck recently by the Reagan administration's leading trade officials -- U.S. Trade Representative William E. Brock and Commerce Secretary Malcolm Baldrige -- in pressing Japan to open its markets to help reduce the U.S. trade deficit.

Brock last week signaled a new tougher tone on trade by the Reagan administration, while Baldrige told reporters that the United States' large trade deficit with Japan "is going to poison the well more and more in the future."

This theme is being stressed as the White House is defining the agenda for a Jan. 2 meeting between President Reagan and Japanese Prime Minister Yasuhiro Nakasone, where the trade deficit is expected to be a major item of discussion.

Olmer's speech, however, was the hardest to date, and the first delivered by a major Reagan administration trade official in Japan since the president's reelection. While he called for Japan to take specific steps to remove remaining trade barriers, Olmer accused Tokyo of continuing to limit imports in areas where the government had promised to reduce barriers.

"For example," he said, "despite Japan's commitment in November 1983 to accept foreign test data for certain medical devices, the Ministry of Health and Welfare has consistently refused to approve nuclear magnetic resonance (NMR) devices, which are similar to CAT-scanners, based on clinical data generated outside Japan.

"As a result, U.S. manufacturers are being forced to repeat these tests in Japan, an extremely time-consuming and costly process. This has caused a delay in obtaining Ministry of International Trade and Industry (MITI) approval and has given Japanese competitors time to narrow the American lead in this technology," he said.

Olmer said the Reagan administration is working now to prevent new Japanese restrictions on imports of high technology and telecommunications products, where U.S. companies "are recognized leaders."

He warned the Japanese that Congress has trade bills on its agenda, including a telecommunications reciprocity bill that would limit Japan's access to the U.S. market. "The future of these bills," he said, "will in part depend on how much progress U.S. business, labor and farm lobby groups think we are making in redressing the trade problems," Olmer said.

He said trade frictions often arise because Japan's decision-making process generally is conducted behind closed doors by bureaucrats and businessmen, with foreigners excluded. He pressed for greater "transparency" in the process and expressed concern that the all-important mid-level bureaucrats draft regulations without considering access by foreign suppliers.