President Carter and his chief Democratic rival, Edward M. Kennedy, engaged in a long-distance debate today as Tuesday's Wisconsin primary drew nearer.

In an interview published in today's Milwaukee Journal, Carter said "Sen. Kennedy, regrettably, has not been completely frank" on inflation. Kennedy, the president went on, has proposed "unworkable" solutions and is "making no effort in the Congress to carry out his own proposals."

In a speech Friday, Carter took an indirect swipe at his opponent, saying that advocacy of mandatory wage and price controls evidences "cowardice and demagoguery." Kennedy is the only presidential candidate advocating mandatory controls to curb inflation.

Kennedy, who arrived here this morning to begin two days of campaigning, reacted calmly and, on the whole, seemed pleased that the president had taken out after him.

The challenger tucked a copy of the Journal into his coat pocket and brandished its banner headline ("Kennedy Misleads Public on Inflation, Carter Says") at every stop today.

"Let me tell you what statements I've been making . . . and find out if they're misleading," Kennedy told an audience at Stevens Point, near the center of the state.

"What I'm saying . . . is that four years ago the rate of inflation was 5 percent . . . Today it's 18 percent and interest rates are 18 or 19 percent. That happens to be the fact of the matter, Mr. Carter, and if you came out of the Rose Garden and talked to people . . . they would tell you about the cruel choices they're facing."

Carter and his wife, Rosalynn, have said the American hostages in Tehran might be endangered if the president were to engage in partisan disputes with his challengers. But the president has granted interviews in some states timed to appear just before primary elections.

Meanwhile, the president's campaign pollster, Patrick Caddell, said data collected over the weekend indicate that the Carter-Kennedy race is "tightening up some." Also, the Carter campaign announced that Vice President Mondale would return here Monday to rebut Kennedy.

In the interview published here, Carter criticized the leading Republican presidential candidate, Ronald Reagan, in passing, but devoted most of his time to attacking Kennedy.

Talking about Kennedy's use of the mistaken United Nations vote on Israel in last week's New York primary, Carter said, "It's obviously highly advantageous to greatly favor the Israeli position . . . as we approach the New York primary.

"I cannot modify our positions or yield to the temptation to mislead the American people or to demagogue an issue just to get a few votes. . . ."

Discussing Kennedy's call for wage-price controls, Carter said, "It's important that the candidates involved not demagogue the issues and not avoid being completely honest on the causes of inflation and what can be done to control inflation."

The president pointed out that Kennedy has proposed both wage-price controls and gasoline rationing during his campaign, but has not introduced legislation to achieve either goal in Congress.