President Reagan telephoned U.N. Ambassador Jeane J. Kirkpatrick yesterday to assure her that his remarks about not having a major foreign policy post open for her were not intended as a rebuke and to reiterate that he still wants to discuss continued service in the administration, informed sources said.

Reagan's gesture came after Kirkpatrick called the White House late Wednesday and canceled a meeting with the president scheduled for yesterday. She cited "pressing business" at the United Nations, but her action triggered speculation that she was angry because Reagan had told The Washington Times that he did not see a foreign policy opening "that would be worthy of her."

In response to queries about Reagan's call, Kirkpatrick issued a statement saying: "As always, the president and I had an extremely pleasant conversation. Any further comment would have to come from the president himself."

The sources, who declined to be identified, also described the conversation as amicable. They added that there was "no substantive discussion" of possible roles for Kirkpatrick in Reagan's second term. Instead, they said, Reagan and Kirkpatrick agreed to discuss her future at a time when the controversy over keeping her in the administration "has cooled down a little."

Conservatives, impressed by Kirkpatrick's advocacy of a tough line against leftist insurgencies in Central America, regard her continued presence in the administration as necessary to counter moderates such as Secretary of State George P. Shultz, and have been urging that she be given a top policy-making post.

Reagan had indicated that she could become a special White House counselor or virtually have her pick of embassies abroad. But Kirkpatrick has let it be known that she is interested only in such jobs as secretary of state or defense, director of the CIA or national security affairs adviser. Reagan has asked the incumbents in all these posts to stay on.

White House press spokesman Larry Speakes, responding to questions about the postponed meeting yesterday, said it would be rescheduled for next week. However, the sources said that, as of last night, Kirkpatrick had no appointment or plans to visit the White House next week, and they indicated that it was likely to be somewhat longer before she and Reagan conferred.

Speakes, peppered with questions about Kirkpatrick's status, reiterated that "there is no opening within the foreign policy area within the White House." Asked if Reagan couldn't make an opening, Speakes replied: "If he wanted to fire somebody, but I don't think he's going to fire anybody."

Speakes also insisted that the president's remarks to The Washington Times had not been intended as a signal of displeasure about the pressures being exerted on Kirkpatrick's behalf. He said:

"She has not expressed any distress, and, if there is any discussion in any quarters, or any distress in the press, I think that would be sadly misinterpreting the president's views. He thinks very highly of her, and he would like to have a position for her in the administration."