President Carter answered his liberal critics in his own party yesterday, asserting that "they are very difficult to please" but that his record in promoting liberal, economic and social policies "will be able to bear their scrutiny."

The President cited his support for several pieces of legislation, including a $4 billion jobs bill he will sign today, and tied these measures directly to his pledge to balance the federal budget by the end of his term. In recent days, liberal Democrats have charged that administration policies are sacrificing economic and social welfare goals in the interest of a balanced budget.

"We consider the realization of the objective of a balanced budget to be tied very closely with the right of people to have a job," Carter said during a press conference. "If we are going to have high unemployment, we are not going to have a balanced budget. So I don't think the criticism was justified and I am very thankful it was confined to one person."

The "one person" the President singled out was Sen. George McGovern (D-S.D.), the 1972 Democratic presidential nominee and the new president of the liberal Americans for Democratic Action.

In a speech to the ADA Saturday, while Carter was in Europe, McGovern roundly criticized administration policies.

"In reviewing economic policy this spring, it sometimes seems difficult to remember who won the last fall," McGovern said echoing the belief of many Democratics that Carter's policies are not much different from President Ford's.

"I don't know that Sen. McGovern's speech to the ADA was mirrored in the objections by any other Democrats," the President replied.

Carter criticized McGovern a second time during the press conference, this time by omission, while discussing a memorandum written last December by Pat Caddell, the Carter campaign pollster.

Caddell had warned the then President-elect that his most serious political opposition was likely to come from within his own party, including traditional liberals such as McGovern and "young 'Turks" such as California Gov. Edmund G. (Jerry Brown.

Carter replied by saying he felt "threatened" by neither man but that he had "a close and friendly relationship with Gov. Brown. He helped me during the campaign."

He did not mention McGovern in that context.

During the press conference, his first since returning Tuesday from five days in Europe, the President appeared even more than normally self-confident, evoking laughter from his questioners with several of his replies.

Asked if there was a danger he would lose the support of liberals in his own party, he said:

"Well, there is always that dancer. I think one of the characteristics of some liberals is that they are very difficult to please. And when some of the groups make a list of things they want, if they get 95 per cent of what they want they can only remember the other 5 per cent."

The Caddell memo, which suggested a political strategy and tactics for the new administration, surfaced publicly just before Carter left for Europe. One of its recommendations was that the new President should concentrate on style - town meetings, for example - because too many incumbents had been defeated for stressing substance over style.

The President said he agreed with Caddell's observation and had deliberately emphasized a style of openness to build up the confidence of the American people in government generally and in him specifically.

After the press conference, Carter chatted with reporters and said that several of the European leaders he had met "deplored the resurrection of Watergate" through the broadcast of David Frost's interview with former President Nixon.

"I personally think that he did violate the law, that he committed impeachable offenses," Carter said of Nixon. "But I don't think that he thinks he did."