President Reagan will announce new action in response to the Polish crisis in a nationally televised speech tonight at 9.

The president's address was still being written last night, but White House officials said "it will advance the situation" and "will be more than an expression of concern."

White House communications director David Gergen said Reagan will speak for 10 to 20 minutes and will combine his statement on Poland with a Christmas message to Americans.

The decision for Reagan to make a speech to the nation on Poland came at the end of a day during which the president held an emotional meeting with Romuald Spasowski, the Polish ambassador who defected Sunday in protest over the military crackdown in Poland.

Reagan had tears in his eyes while Spasowski and his wife wept openly during a 15-minute encounter in the Oval Office.

"I'm very proud that he's here in this office," Reagan said of his guest. "I think we're in the presence of a very courageous man and woman who have acted on the highest principle. And I think the people of Poland are probably very proud of him also."

Reporters asked the president if he had given Spasowski any encouragement about options the United States was exploring to aid the Polish people. Reagan replied: "Well, the ambassador is aware of the things that we've been talking about, what we're trying to do."

Later in the day, after Reagan presided over a National Security Council meeting on Poland, officials would say only that the administration's position was hardening. The only action Reagan has taken is to suspend aid to the Polish government; he opened his news conference last Thursday with a strongly worded statement on Poland that did not propose any actions.

Edwin Meese III, Reagan's counselor, told reporters before the NSC meeting that "we're looking at an array of political, diplomatic, security and economic measures that might be taken."

One administration source said that some matters remain to be decided in the hours before the president's speech and that it is unlikely Reagan will be able to reveal the "full panoply" of U.S. responses.

Among the U.S. actions reportedly under consideration are a halt of all economic help for the Polish government, including relief from scheduled payments on official debt. European governments and banks, which have a much larger financial stake than does the United States in the $26 billion Polish debt to the West, are thought to be less inclined than Washington to take drastic actions.

A delegation of State Department and Treasury officials headed by Assistant Secretary of State Lawrence S. Eagleburger is in Europe discussing U.S. options with European leaders.

Sanctions against the Soviet Union, which Reagan has accused of supporting and having advance knowledge of the martial law crackdown, present an even more complicated problem than actions against Poland in the absence of visible and dramatic evidence of Soviet intervention.

Reagan is reported to be weighing new limitations on trade and sales of U.S. technology to the Soviet Union. As he left a White House meeting yesterday, Agriculture Secretary John R. Block ruled out an embargo on agricultural products alone. Reagan lifted the grain embargo imposed by President Carter in retaliation for the Soviet invasion of Afghanistan.

Meese, the top White House adviser on foreign policy, said: "Our main concern is the Polish people and what is going to be most helpful to them. The president has been very prudent and very careful in the way he has approached this, not from a lack of options--there have been plenty of options--but from a desire not to do anything that would jeopardize the situation of the Polish people."

Three major scientific organizations yesterday protested the repression and arrest of researchers in Poland. National Academy of Sciences president Frank Press cabled his counterpart in Poland expressing the "collective horror" of the U.S. scientific community over repression there. The American Association for the Advancement of Science protested arrests and the Federation of American Scientists warned on behalf of the world's scientists that "the Polish government suppresses Polish scientists only at its own peril."

Meanwhile, Elliott Abrams, the assistant secretary of state for human rights, said the administration has no confirmation that Polish Jews are being singled out for special punishment, but said it is concerned by such reports and is watching the situation closely.