Senate Majority Leader Robert C. Byrd yesterday wrote off any chance of a tax cut measure clearing Congress before the November election.

"I don't see sufficient support" for the idea in either house of Congress or in the Carter administration, Byrd told his regular Saturday news conference. He added that "in all likelihood" a lame-duck session of Congress will convene after the elections to work on taxes and other measures.

The West Virginia Democrat praised the $40 billion tax package offered last week by the Senate Finance Committee, saying it would benefit people with low incomes, in contrast to a Republican proposal that Byrd charged would help the rich.

"There should be a tax cut in 1981, but its timing and impact on inflation in this country need to be considered very closely," Byrd said.

Byrd indicated that he has almost abandoned hope of balancing the budget, a goal he had fervently supported earlier this year.

"Congress made every effort to do it . . . and if we don't it will be because of changes in the economy, not from lack of will," Byrd said. The budget resolution, which also will have to wait until the lame-duck session, now anticipates an $18 billion deficit, he said.

Turning to politics, Byrd called on Republican presidential nominee Ronald Reagan to clarify his stand regarding U.S. relations with China and Taiwan. In calling for upgraded diplomatic contact with Taiwan, Byrd said, Reagan is "attempting to roll back the waves of history . . . catering to the very right-wing segment of the [Republican] party."

He noted that Presidents Ford, Nixon and Carter all have had the same "one-China" policy that does not recognize Taiwan, and that the People's Republic of China is alarmed at Reagan's recent statements.

"According any official status now to Taiwan would seriously jeopardize our policy of normalization with the People's Republic," Byrd said.

Byrd again attacked Republican campaign literature as inflammatory and said Democratic Party unity will continue to improve as the fall campaign gets rolling. He said he never doubted that Sen. Edward M. Kennedy (D.-Mass.) would come around to supporting President Carter for re-election.

"With his [Kennedy's] leadership, other Democrats that supported Kennedy will in the main support the nominee," Byrd said. "The president . . . is going to win this election."

Independent candidate John B. Anderson is not a serious presidential contender, Byrd continued.

"I don't think he has the chance of a snowball in Sheol -- that's capital S-h-e-o-l," meaning hell, Byrd said. "As time goes by and debate sharpens, people will understand that it's either going to be Reagan or Carter, and to vote for anyone else is to cast away that vote."