President Reagan has given a new assurance that he will not agree to a cutoff date for U.S. arms sales to Taiwan, Sen. Barry Goldwater (R-Ariz.) said yesterday.

Goldwater, in a telephone interview from Phoenix, said Reagan made the statement to him in a June 18 Oval Office meeting that was also attended by Vice President Bush and presidential counselor Edwin Meese III. Goldwater said he had asked for the top-level meeting after hearing from representatives of Taiwan that the State Department was preparing draft communiques containing "a time certain" for ending arms sales to Taiwan.

The report from Goldwater came as the administration moved into a new phase of its policymaking on the controversial and complicated Taiwan arms question, the subject of a serious dispute between the United States and the People's Republic of China for the past six months.

Recommendations from outgoing Secretary of State Alexander M. Haig Jr., sent to the White House earlier this week in a bid to settle the issue, were considered by Reagan Thursday, according to official sources.

The president evidently did not accept Haig's proposals in full, because the sources said the recommendations are being sent back to the State Department and the National Security Council for further work.

William P. Clark, White House national security affairs adviser, is quoted in a participant's notes of a June 23 Capitol Hill meeting on the issue as saying that there will be "no backing away" from Taiwan and "no time limit on the sale of arms" to the island bastion.

Clark, according to a participant in the meeting with 13 conservative members of the Senate and House, also said that "the president will not abandon our moral and legal commitments to Taiwan, and at the same time he values good relations with the People's Republic."

Clark told the group, according to the notes, that the NSC had rejected "many proposals" for a time limit on the sale of arms to Taiwan.

Goldwater, who visited Taiwan in early June, said he was visited on his return by a Washington representative of Taiwan President Chiang Ching-kuo, who reported that the State Department had prepared two "draft communiques" for settlement of the Sino-American dispute about arms sales to Taiwan.

Goldwater said he was told the communiques would involve a time limit on the sales, which in his opinion would be inconsistent with U.S. promises under the Taiwan Relations Act.

After being told by a State Department representative that no such communiques had been prepared, Goldwater said, he asked to see Reagan on the issue. The senator quoted Reagan as saying, "I never heard of the communiques, and I wouldn't sign them if they came to me."

Chinese officials, who at one stage demanded a cutoff date for U.S. arms to Taiwan, are reported no longer to be making such a demand.

Gary Jarmin, executive director of the American Council for a Free Asia, a lobby group favoring strong U.S. ties with anti-communist Asian states, said he had learned from State Department sources of two proposals prepared for transmission to the White House several weeks ago.

In one option, he said, the United States would renounce a policy of "long-term arms sales" to Taiwan, agree to a qualitative and quantitative ceiling on sales and speak of a gradual reduction in future sales. The other option contains more emphatic statements that the sales "will eventually be terminated," Jarmin said.