President Reagan, breaking administration silence on the Philippine presidential elections, yesterday played down reports of fraud there and said results so far prove that "there really is a two-party system, obviously good" in the Philippines.

Once a government is chosen, "we would like to have the same relationship -- historic relationship -- we've had with the people of the Philippines and with their government," Reagan told The Washington Post in an interview.

Reagan added, however, that he would reserve judgment on the degree of fraud until he hears the report today of a 20-member official observer delegation headed by Sen. Richard G. Lugar (R-Ind.).

"Whether there is enough evidence that you could really keep on pointing the finger or not, I don't know, but I'm sure that, you know, even in elections in our own country there are some evidences of fraud in places and areas," Reagan said.

"I would foresee that now that there really is a two-party system, obviously good, with millions of people going to the polls and voting on both sides, that this is the beginning of what could be the answer to their form of government."

The president's remarks seemed to move the administration closer to backing the election outcome in the Philippines, no matter what the finding on fraud, than officials were willing to go earlier.

That impression was reinforced by a senior administration official, who told reporters earlier that U.S. policy favored nonviolent cooperation between the two sides.

"The main thrust of our statement is not to have violence, not to have demonstrations in the street just because you didn't like the election outcome ," said the official, speaking on condition that he not be identified. "Get on the team and work with the government to form a government, whether it's Marcos or Aquino."

Those remarks followed recent announcements by challenger Corazon Aquino that she will lead daily nonviolent demonstrations if she is denied the victory she claims over President Ferdinand Marcos. She has also said she is not sure she would be able to control her disappointed followers.

White House spokesman Larry Speakes, asked if the administration statements were intended to give tacit backing to the election results, said, "The Filipino people will determine if they are legitimate."

Reading from a statement, he said, "We've seen the reports of violence and fraud. We're concerned." However, he said, "the outcome of the election is not clear and the facts are not in."

Returning to Washington last night, Lugar refused to comment on the commission's findings, but Sen. John F. Kerry (D-Mass.) said there was a "total breakdown and slowdown" in the vote-counting, and that the problems he observed made it "very difficult for any semblance of credibility to come out of the election."

Officials have said repeatedly they would await the verdict of Lugar's group, the citizen poll-watcher group Namfrel in Manila, and the Roman Catholic Church in the Philippines before announcing their own findings.

The officials' apparent shift towards backing the election caused some consternation at the State Department. One official noted that the White House "had the option of calling on Marcos to observe the people's will" and had not done so.

Another senior official said later, however, that the statement was intended to send Marcos the message that he has strong opposition and should listen to Aquino in setting up a new government. It was also intended to tell Aquino that she would have more impact working with Marcos than in launching demonstrations.

Reagan said before last Friday's balloting that he would consider increased U.S. aid to the Philippines only if there were a credible election followed by meaningful economic and military reforms. An ad hoc interagency group of decision-makers, some of them expressing "disgust, dismay" over the fraud reports, has been meeting almost nonstop at the State Department since Friday to work out policy options.

"We have to leave the option open" to condemn the election as invalid to remain credible to the Filipino people, one official said. He expressed puzzlement with the statement by the unnamed White House official promising to work with whatever government is elected. "I don't know what the official was trying to say."

Another official said policy options "range just about from swallowing all this apparent fraud whole to telling the Filipinos we'll help overthrow the government." Official silence was "trying to buy time" for Filipino poll-watchers to sort out the vote, he said.

However, officials have also said repeatedly that they will not cut off U.S. aid to the Philippine armed forces, who are fighting a growing communist insurgency.

The main U.S. concern is its huge Navy and Air Force bases in the Philippines, which anchor U.S. strategic interests in Asia. Their continued operation requires a strong and friendly government as host.

"The main thing is that we have a strong and stable Filipino ally in the Pacific for the United States, and a strong government is essential to maintain a peaceful resolution of the problems that face the Filipinos," the senior administration official said.

The combined effect of the statements was to increase the political weight of the report the team of observers is to make to Reagan today.

In Manila, Lugar pleaded with Marcos to "let the count continue" because the election was "teetering on the brink of disaster." The administration was reported to be making the same point to Marcos privately, warning that time was running out if the Filipino people and the U.S. public are to retain any faith in the election results.

At a news conference before leaving for Washington, Lugar said a valid election was only "a small, glittering hope" and that "in the event that things do not turn out well, our president is going to have to make some major decisions."