There were signs yesterday that President Reagan may have misspoken on Tuesday when he told Republican senators that Federal Reserve Chairman Paul A. Volcker had predicted interest rates would fall three or four percentage points by summer.

Volcker had previously said in congressional testimony he thought interest rates would begin to come down--he did not predict how much--if Congress took action to reduce spending and avoid the near $100 billion budget deficit the administration now foresees next year.

But Reagan, in his session with the senators who want to reduce his recommended deficit to help bring down the interest rates now choking the economy, made no mention of any qualifications when he reported Volcker's private assurances to him, congressional sources said.

The White House sought yesterday to play down the president's remarks. Deputy White House press secretary Larry Speakes said Reagan wishes they had not been disclosed and does not intend to talk anymore about his one-on-one meeting with Volcker two weeks ago.

"The president made a statement privately which I do not want to disclose," Speakes said. "But he did make a statement which I can't disclose."

Senate Republicans confirmed again yesterday the reports of what Reagan had said. They said the president's comments came in response to Senate Majority Leader Howard H. Baker Jr.'s expression of concern about continued high interest rates.

Senate Republicans have proposed cuts in military spending and adjustments to the president's program of tax cuts, to reduce the deficit and hopefully bring down interest rates. Reagan, while indicating a willingness to consider alternatives, reaffirmed his strong commitment to his basic budget.

Volcker refused to comment yesterday but a Fed spokesman referred reporters to the chairman's previous on-the-record comments that tied a reduction in interest rates to reduction of the deficit.

Speakes said Reagan had called Volcker Tuesday after reports of the president's remarks to the senators began appearing on wire services.

"I wouldn't characterize it as an apology," Speakes said.

Speakes said he had spoken yesterday with a Volcker aide to find out what the chairman remembered saying to Reagan. According to Speakes, the aide said Volcker told him that "he didn't have a specific recollection of what he'd said in the meeting."

Speakes said the administration is making no predictions itself about when interest rates will begin to drop.

"Certainly they're going to come down. They're already coming down," he said referring to the decision this week of Chase Manhattan and other banks to lower the prime rate from 16 1/2 to 16 percent.