Republican Party Chairman Bill Brock said yesterday that it is time for free political debate on the question of freeing American hostages in Iran and on other foreign policy issues.

"I think the moratorium on that issue is over and, if it isn't, it ought to be," Brock told a news conference during the two-day Southern Republican Leadership Conference in New Orleans.

"It is crucial that we talk about how we got into this mess and how we are going to get out of it," he said.

Brock praised President Carter's State of the Union warning that any Soviet move toward the oil-rich Persian Gulf area would not be tolerated by the United States.

"I don't think that position was taken just to make political hay," the GOP chairman said. "I think it was desperately needed . . . I hope it represents a true change of heart."

Ronald Reagan escalated his attack on President Carter's "utterly ridiculous" foreign policy yesterday and called on Carter to disavow the SALT I and SALT II treaties until Soviet troops are withdrawn from Afghanistan.

At a news conference at the Southern Republican Leadership Conference in New Orleans, Reagan blasted Carter for adhering to the terms of the arms treaties while the Soviet Union invades a free country.

"It just seems utterly ridiculous to be talking about unilaterally obeying what is supposed to be an arms limitation with a country that has embarked upon an aggressive imperialism outside its own borders," Reagan said.

He said Carter was sending "contradictory signals" to the Soviets by pledging to uphold the terms of SALT I and SALT II, even though they lied to him and ignored his warnings to stay out of Afghanistan.

"Mr. Carter is risking nuclear confrontation by sending contradictory signals to the Soviet Union," Reagan said.

"The Soviets only see weakness in a president who clings to the unilateral observance of the fatally flawed SALT treaties," he said.

The Democraic Party yesterday decided to let Wisconsin hold its controversial open presidential primary April 1 in defiance of party rules.

The move was seen as a victory for Wisconsin Democrats, who have been united in opposing national party moves to do away with "crossover" voting, which permits Republican to vote in the Democratic primary.

The party's executive committee voted to pursue its legal challenge of the primary to the Supreme Court. But it tabled an effort to impose an alternative delegate selection system on the state.

This means that the Wisconsin primary, sometimes a decisive stepping stone in the presidential selection process, will continue in 1980 just as it has every four years since 1912.

Republican presidential hopeful George Bush said yesterday that President Carter's emphasis on human rights may have conflicted with some of the nation's strategic interests.

In a campaign appearance in Milwaukee, Bush said Carter must make the point that both strategic and human rights issues are being considered in formulation of foreign policy.

"I don't think Jimmy Carter has done that," the former U.N. ambassador said. "I think everything has been cloaked in human rights."

John B. Connally's campaign manager has given up day-to-day operation of the campaign to work exclusively on policy and strategy.

Eddie Mahe Jr. said he had long wanted to rid himself of routine operation of the headquarters. Campaign spokesmen said administrative responsibilities would be taken over by Charles Keating, who joined Connally's effort late last year.

"I wanted to get away from the day-to-day crap of writing letters and running postage meters, and get back to doing the things I like doing best," Mahe said.

The Connally campaign underwent a major reshuffling last fall, and aides claimed that the lost time caused them to get a late start in their attack on Ronald Reagan's base of support.

Ronald Reagan's presidential campaign yesterday accepted a federal check for $100,000, ending weeks of internal debate over whether Reagan should accept federal matching funds and the spending limits that go with them.

It was the Reagan campaign's first such check. Its second will be far larger. Reagan aides also delivered to the Federal Election Commission the largest single matching-funds request ever filed.

The filing, delivered by truck and contained in three large cardboard cartons, asks for almost $2 million from the U.S. Treasury.

The decision reflects the Reagan campaign's realization that its fundraisers could not gather enough contributions to run the campaign without federal money, campaign treasurer Bay Buchanan said. "Our feeling was, don't take matching funds until you have to," she said.

"Sure, losing Iowa definitely affects fund-raising," she said. But the decision to accept matching funds might have been made even if Reagan had won, she added.

Michigan Democrats will be selecting their 1980 National Convention delegates in a closed caucus meeting, but California Gov. Edmund G. (Jerry) Brown Jr. is threatening to buck the System. Brown will put his name on the primary ballot in the state -- the "beauty contest" -- even though the results will be meaningless in terms of convention delegates.

State party leaders asked the three Democratic presidential candidates to ignore the Democratic primary here, back when the state legislature dissolved the primary as the way to select delegates. But Brown is calling the caucus system an unfair way to pick delegates, and he says he will run in the "beauty contest" and go to court, if he wins, to collect his fair share of the delegates.

Brown, in Detroit to tape a local television interview show, said the caucus system amounted to a "poll tax," since only dues-paying Democrats can attend. The dues are normally $10, with full-time students paying $3.

"It is improper to impose a poll tax or fee on people who are selecting their candidate for president," Brown said. "The Supreme Court struck that down in the South. I certainly wouldn't want to see it resurrected in the North in the form of this quasi-poll tax."