Republican presidential candidate George Bush said tonight that he had "no recollection" of receiving a $6,000 cash gift from Richard and Pat Nixon in his 1970 Texas Senate campaign and "thus I know it's not true."

Bush reaffirmed and strengthened the denial that was included in today's Washington Post report that former Nixon aide Jack A. Gleason described such a contribution to the Watergate special prosecutor in 1974.

"That fellow says he gave me $6,000 from Mr. and Mrs. Nixon," Bush told a news conference here on his first stop after returning from a campaign swing to Puerto Rico."I'd remember that, and I have no recollection of it, and thus I know it's not true."

Bush said he was "absolutely certain" of his memory and added that "nobody in our campaign has any recollection" of such a gift.

The Post article said that Gleason had given testimony on the matter to Watergate investigators, who were looking into the "Townhouse Fund," an operation he ran as a device for channeling campaign funds to Nixon-backed Senate candidates in 1970.

Previous reports had centered on $106,000 in funds given to the Bush campaign, but this was the first allegation that Bush had received cash personally.

According to federal officials, the matter was never prosecuted because the transactions were not regarded as illegal under existing statues. In the case of the alleged cash contribution, officials also said there was a lack of corroborative testimony.

Gleason had told the Post that "after 10 years, I would not feel confortable testifying under oath about anything. My recollection is not that specific, but every memory I have is that I handed the money to him personally."

Bush said this indicated that Gleason's memory was "shaky" and said -- as he had before -- that "every penny" contributed to his unsuccessful Senate campaign had been reported according to law.

There was no immediate indication that the Gleason allegation would become a significant issue in the Feb. 26 New Hampshire primary.Bush was asked only one question about the matter at the news conference here.