President Reagan said yesterday that he is "optimistic" that the superpowers will reach an arms control agreement this year on U.S. and Soviet intermediate-range nuclear missiles in Europe because Soviet leader Mikhail Gorbachev is no longer requiring abandonment of a U.S. missile defense system as a condition.

In an interview with The Washington Post, the president called the new Soviet position, conveyed in a Kremlin meeting with Sen. Edward M. Kennedy (D-Mass.), "a hopeful sign" although there are "points that have to be worked out."

Addressing a range of foreign and domestic issues in the Oval Office interview, Reagan said he would "go all out" in an effort to obtain military aid for the Nicaraguan rebels. He said the rebels have "to be able to protect themselves" against the ruling Sandinistas, who are receiving "extensive aid" from the Soviet Union and Cuba.

The president also gave an animated denunciation of "those cartoons that run every other week in the paper with [Defense Secretary] Cap Weinberger and a toilet seat around his neck." Reagan said the recommendations of the commission he appointed on defense management will answer the "propaganda" of those who depict the Pentagon as wasteful and inefficient.

In his discussion of a prospective agreement limiting intermediate-range missiles in Europe, the president raised the possibility that Gorbachev had always intended to pursue such a pact without insisting that the United States scrap its missile defense program known as the Strategic Defense Initiative, often called "Star Wars."

Reagan said it isn't clear whether Gorbachev "dropped it or . . . never intended it to be there." The president pointed to the joint statement he and Gorbachev signed at their Geneva summit calling for "early progress, in particular in areas where there is common ground." One of the two "areas" cited in the statement was "the idea of an interim INF intermediate-range missile agreement."

"So maybe he's just now confirming that he meant this all the time," Reagan said. "But it is progress in our eyes."

At a Washington news conference Saturday after he returned from Moscow, Kennedy said Gorbachev had tied the timing of his next summit with Reagan to progress toward an agreement on the intermediate-range missiles.

Reagan said yesterday that he "can't believe" that Gorbachev would want to scrap the summit and said the Soviet leader had agreed at the close of their Geneva meeting that there should be a second summit in the United States this year and a third summit in the Soviet Union in 1987. The president said he continues to want the second summit to be held in June or July of this year so that it doesn't interfere with U.S. elections this fall.

"They made one suggestion of a later date but they haven't pursued it at all," Reagan said. "And we told them why we didn't feel we could do that."

White House spokesman Larry Speakes said yesterday that "we very much appreciate" Kennedy's report on his meeting with Gorbachev. Kennedy met Saturday with John M. Poindexter, Reagan's national security affairs adviser.

In his interview yesterday, the president said that the Soviet positions on British and French nuclear forces and on Soviet intermediate-range missiles in Asia remain obstacles to an agreement.

Gorbachev's Jan. 15 proposals removed a longstanding roadblock to an INF agreement regarding British and French nuclear forces. In the past the Soviets had insisted that these forces be counted against the total permitted the United States in Europe. The new Soviet position simply asks that the British and French forces not be increased from their present level, while the Soviets and Americans steadily reduce their European-based missiles to zero. The Reagan administration had earlier proposed eliminating European-based missiles, so the two superpowers' positions now have much in common.

Reagan said yesterday, in reference to the British and French, "We don't think that we're in a position to negotiate for somebody else."

The president said the United States had already submitted a counterproposal to the Soviets. But a spokesman said later that he was referring to the Nov. 1 proposal made to the Soviets in Geneva.

The United States has not responded to the Jan. 15 Soviet offer, and White House officials said yesterday that none will be made until Reagan has met with Ambassadors Paul H. Nitze and Edward L. Rowny, who will return to Washington this week after conferences with U.S. allies in Europe and Asia.

Reagan was unyielding in his insistence that the Nicaraguan counterrevolutionaries, or contras, receive military aid. Congress last year gave the rebels $27 million, which expires March 31, but limited the money to nonlethal aid and prohibited it from being distributed through the Central Intelligence Agency or Defense Department.

The president's pledge to go "all out" for assistance to the rebels came in the wake of warnings from House Republican leaders to the White House that the contras could not maintain a military presence in Nicaragua without more than nonlethal aid. House Minority Leader Robert H. Michel (R-Ill.) and Rep. Dick Cheney (R-Wyo.) are expected to send a letter to the White House today calling for a "major personal commitment" by Reagan to the "armed democratic resistance" including a legislative package of substantial military aid and removal of restrictions on CIA funding control.

Reagan said he still believes a negotiated settlement between the Sandinistas and the rebels is possible during his presidency.

The president also said his administration is "perfectly willing and ready to help in any way you can" to bring about a democratic government in Haiti after the rule of Jean-Claude Duvalier, who fled to France last week. When Reagan was asked whether this meant resuming the aid that had been stopped because of Duvalier's violations of human rights, the president turned to White House chief of staff Donald T. Regan. "We're in the process of reviewing that when see what the new government does," Regan said.

The president responded with some acerbity when he was asked to comment on a statement by his former budget director, David A. Stockman, that big government deficits were caused not just by liberal Democrats but by Republicans, including the president. "Well, my memory doesn't track with his because every year that I've been here we have tried to get the elimination of some programs [and] reduction of others," Reagan said.

The president refused to accept any personal blame for the record federal deficit, blaming the Democrats, while taking credit for economic growth, which he called "the greatest recovery that we've ever had in the last 50 years."

Reagan answered questions calmly during most of the 26-minute interview. But he became noticeably heated when asked to comment about polls that show rising public skepticism about defense spending. The president said this was because people have been hearing "a constant drumbeat of propaganda about defense scandals and defense spending and that it is all wasted and so forth.

"And there's only one way left," Reagan continued. "We're going to go direct to the people and tell them the truth. There wasn't any $600 toilet seat. And all those cartoons that run every other week in the paper with Cap Weinberger and a toilet seat around his neck. That's the same price that TWA and Delta and United pay. It is a molded cover [for] the entire toilet system. And yes it does cost about that much."

The president also denounced stories about "the $400 hammer" and the "$6,000 coffeemaker," which he called "an entire hot-cooking system" and said the government was paying less for it than do commercial airlines.

After Reagan defended Weinberger's management, he was asked why then he needed to appoint a separate investigating commission, headed by former deputy defense secretary David Packard.

"We decided that in the face of this propaganda there was only one answer: Bring in an outside commission and let them look at the whole thing and then come back and tell us and tell publicly what they've found," Reagan replied.