Nagasaki, Japan — Recent actions by the United States Congress on Taiwan have ''destroyed'' the good atmosphere necessary for the projected exchange of visits by President Reagan and Chinese Premier Zhao Ziyang, Foreign Minister Wu Xueqian said.
Mr. Wu stopped short of saying the exchange of visits would not take place. But in an interview with The Christian Science Monitor here Tuesday, the foreign minister made clear that the Chinese government was far from satisfied with explanations so far made by Washington.
Three ''unpleasant incidents'' have occurred recently in Sino-American relations, Mr. Wu said. The first was a US Senate resolution on the future of Taiwan. The gist of it was that reunification of Taiwan with the mainland must be peaceful and must have the consent of the Taiwanese people.
The second was President Reagan's remark while in Japan that the US would not abandon old friends while making new ones, and his characterization of Taiwan in this context as the ''Republic of China.'' China had made an oral protest over this remark and a written protest over the Senate resolution, Mr. Wu said.
The third unpleasant incident, over which China has also made a written protest, was an amendment to an appropriations bill for the International Monetary Fund passed by both houses of Congress, Mr. Wu said.
The amendment refers to Taiwan as the Republic of China and says the US will defend Taiwan's seat in the Asian Development Bank even if China becomes a member of the bank. (The ADB is just about the last international organization in which Taiwan is a full member and China is not.)
Mr. Wu is accompanying Hu Yaobang, general secretary of the Communist Party of China, on a week-long visit to Japan. The atom-bombed city of Nagasaki is the general secretary's final stop.
After the interview, Mr. Wu accompanied Mr. Hu to a wreath-laying ceremony at the atom bomb memorial, then visited Mitsubishi's giant shipyard and spoke at a farewell press conference before emplaning for Peking late in the afternoon.
Mr. Hu has also spoken publicly about having to perhaps ''reconsider'' the Reagan-Zhao exchange of visits. But Mr. Wu's statement that the good atmosphere necessary for the visits had been ''destroyed'' is the strongest so far made by a Chinese official.
Mr. Wu, who had a very cordial visit to Washington in October, recalled that Sino-American relations began to improve in June when the US announced it was relaxing restrictions on high-technology sales to China. Thereafter improvement continued, until the two sides were able to announce plans for a visit by Zhao to the US in January and by Reagan to China in April next year.
''It is important that the exchange of visits between the two leaders take place in a good atmosphere,'' Mr. Wu said. ''But before these visits could happen, the US Congress has taken these two actions concocting two Chinas. This has obviously destroyed the atmosphere necessary for the visits.
''So in our protest note to the US, we have demanded that the US government clearly express its attitude towards these two actions of the Congress.''
''We want Sino-American relations to continue to improve,'' Mr. Wu said. ''The main obstacle is Taiwan. The US Congress has taken actions that are not good, in fact, that are very bad. These actions not only do not help to remove the obstacle hampering improvement of Sino-American relations, but make the obstacle even larger.''
At a joint press conference with General Secretary Hu held later in the day, Mr. Wu was asked to comment on a statement by deputy White House spokesman Larry Speakes that Reagan intended to sign the appropriations bill containing the reference to the ''Republic of China.''
(In his statement, Mr. Speakes affirmed that the US recognized only one China , the People's Republic of China, and that Mr. Reagan would make a statement to this effect when signing the bill. The President did not intend to veto the bill , Speakes indicated.)
''I think the statement is contradictory,'' Mr. Wu said. ''On one hand, it says that the US government recognizes only one China, the PRC (People's Republic of China). On the other hand, it says that President Reagan intends to sign the appropriations bill passed by the two houses of Congress. This bill is yet another example of trying to concoct two Chinas. The White House spokesman's statement cannot help but make one feel that the American government, with regard to the Taiwan problem, once again is not matching words with deeds.''
He then repeated, ''For Premier Zhao's visit to the US to take place, there must be a good atmosphere.'' US-China landmarks 1972, Feb: Nixon visits China. Shanghai communique begins normalization. 1976, Sept: Mao Tse-tung dies. 1979, Jan: US, China establish diplomatic relations. Deng Xiaoping to US. April: Taiwan Relations Act pledges "sufficient" US arms to Taiwan. 1981, Jan: President Reagan takes office. June: Haig visits China. 1982, May: Bush visits China. Aug: US-China statement on reducing US arms sales to Taiwan. 1983, Feb: Shultz visits China. June: US permits sale of "dual purpose" technology to China. Sept: Weinberger visits China. 1984, Jan: Zhao Ziyang due to visit US. April: Reagan due to visit China.