The New York Post yesterday moved toward settling its labor problems and resuming publication this week while The New York Times and Daily News said they would continue to hold out for the concessions they have demanded from striking pressmen.

The pressmen ratified a settlement with the Post yesterday under which they will return to work at Rupert Murdoch's Post and the paper agrees to grant them a final contract on whatever terms The Times and News eventually agree to.

"We are saddened that the Post has apparently changed its mind about achieving its pre-strike demands. However, the fact that it is publishing is no more material to our well-being than the publishing of the Daily Metro, a strike newspaper that Mr. Murdoch has supported," the News said in a statement.

A spokesman for The Times, John Pomfret, said that Murdoch's defection from the publishers' joint position would not affect The Times' at the bargaining table.

William Kennedy, the president of the pressmen's union which struck the three papers 56 days ago, told a press conference that The Times was the architect of the strike and that Murdoch had been reluctantly drawn into taking a strike by his fellow publishers.

Kennedy said Murdoch had voted against posting the work rules that would reduce the number of pressmen at each paper. The posting caused pressmen to walk out.

"That's simply untrue," Pomfret said. Jonathan Thompson, a spokesman for the News, said: "No action was ever taken that was not unanimously agreed to by the three publishers."

Murdoch, who could not be reached, appears to be aiming for short-term financial goals at the expense of the other papers.

Only about 150 of the 1,600 pressmen Kennedy represents work at the Post, and Murdoch apparently decided that it was worth breaking with the other publishers and perhaps thereby damaging their bargaining position in order to be, for a while at least, the only regular paper printing.

The Post said held bargaining sessions yesterday with the stereotypers, The Newspaper Guild and the machinists in its hurry-up effort to get back into business. Union leaders said they believe the Post could appear as early as tomorrow if it settles with all its unions.

Although Kennedy said he might reach agreement with The Times and News within two weeks, the basic issue of the strike has been unaffected by Murdoch's decision to go it alone.

The publishers insist that their pressrooms are overmanned and that pressmen run up unnecessary overtime. The union rejects their claims and has refused to consider plans for reducing the number of pressmen employes.

Throughout the strike, Kennedy has made no secret of his hope that the publishers' solidarity would splinter so that he could negotiate with each paper separately. If The Times and News were to abandon their pre-strike positions, however, they would have suffered the losses of a lengthy strike for no gain, and both insisted yesterday that they have no intention of yielding quickly because of the resumed publication of the Post.

Theodore Kheel, the labor negotiator who has been called into the strike talks as an adviser to the affected unions, yesterday rejected the idea that Murdoch's defection made an early settlement more likely.

"If you detect a feeling of optimism," he told a questioner, "now detect something that I don't detect."