Walter Cronkite, television's premier newscaster for the past decade, has told CBS News that he wants out as anchor of the CBS Evening News no later than the expiration of his current contract in November, 1981.

Cronkite, 63, emphasized yesterday that he has no intention of leaving CBS at that time but does want to drop the daily deadline grind of the Evening News, preferably even before the November, 1981 deadline.

"I'd like to be able to step out right now," he said yesterday, but commitments for the 1980 presidential election year bar such an early departure.

In recent months, however, reports have gotten back to CBS News that both Dan Rather and Roger Mudd, two of the prime candidates eventually to succeed Cronkite as anchor of CBS Evening News, have been courted seriously by rival news organizations at both ABC and NBC.

Cronkite speculated yesterday that it was because of the "pressure" from rival networks that CBS news officials approached him two or three week ago and said, "'Hey, we're in a little bit of a bind.' They wanted to know what my intentions were.

"I told them that I'd like to be able to step out right now," Cronkite said, "but they won't let me do it right away." Apparently his decision to leave the Evening News, perhaps as early as next summer, followed these most recent discussions.

A report out of New York had all three networks offering Rather a package of $8 million for five years, with ABC News even throwing in the title of "managing editor" of World News Tonight, the same title Cronkite himself holds at CBS Evening News.

Moreover, rumors circulated for months in broadcasting circles that Mudd had already been assured by CBS News he was to inherit Cronkite's job -- but only when the latter chose to leave.

Sources in New York said yesterday, however, that Cronkites's firm decision to leave sometime in 1981 has changed the CBS equation in favor of Rather, who must now seriously consider current offers from CBS that include the weeknight anchor position.

Recently, Rather was reported leaning towards ABC News, where president Roone Arledge is bent on mounting a serious challenge to CBS News over the next few years.

These sources indicate that neither Rather nor Mudd has been offered anything like the reported $1.6 million a year by any network.

"It's more like $500,000 a year," one network official told a reporter yesterday.

Network officials have long maintained, and reemphasized yesterday, that Cronkite, who has kept the CBS Eevening News No. 1 in the ratings since 1970, when Chet Huntley retired from NBC News, could have the CBS anchor job as long as he wanted it.

But Cronkite said he had urged network officials "for a couple of years to move ahead with the plans for succession and I've told them it would be better for them if I stepped down earlier [than November, 1981].

"But," Cronkite added, "they couldn't bring themselves to make the decision."

Those outside overtures have increased the pressure on CBS News to open negotiations with Rather and Mudd, both of whose current contracts expire in May 1981, regarding their intentions.

The pressures on CBS increased particularly since the prize of inheriting the chair of the No. 1 TV anchor in America has to figure in both Mudd's and Rather's calculations concerning their futures at CBS.

As for his future, Cronkite says he is looking forward to a time at CBS when he can do specials, work on elections and, in particular, pursue the possibilities of "Universe," CBS News' science half-hour which recently received a commitment for six more programs with Cronkite as anchor.

"I'd like to do some deeper things." Cronkite said yesterday. "i'd like to do more series like the [late night foreign affairs] series we did last week.

"I have no intention of leaving the air, it's just my intention to slow down a little and not be frozen to the daily grind.

"i'd like to do some of the same kind of things that Jack Chancellor wants to do at NBC before I hang up the boots."

Cronkite revealed yesterday that he tried to blow out of the Evening News in the spring of last year. He'd planned to return in the fall of 1979 and devote his time to the upcoming political campaigns, minus the nightly news deadlines. But the network mixed that idea.

Instead, Cronkite said, they "gave me a new contract through November 1981, with options for annual renewal.

"I'll sign it," Cronkite said, "but I don't think there's any likelihood it will include me on the CBS Evening News. It's just not in my plans to continure with the EVENING News."

Cronkite, who will be 64 in November, took over the CBS EVENING News in 1962 when it went to a half hour.

But it wasn't until Chet Huntley's retirement in 1970 broke up the NBC News team of Huntley and David Brinkely that CBS moved into first place over NBC in the ratings.

By that time, however, the avuncular Cronkite had already established himself as an imposing personage on TV, anchoring specials on space shots, weeping on camera during the coverage of President Kennedy's assassination, conducting interviews with major political figures of the time and accompanying American presidents on Major foreign trips.

His "and that 's the way it is" has become probably one of the most familiar TV trademarks since the medium was established.

In recent years, he has also been one of the most highly-paid talents, with estimates of his annual salary ranging to $650,000 plus liberal vacation time, rewards which CBS executives have long considered one of the best investments the network has ever made.

Mudd yesterday was enroute to Boston to cover political activities for CBS Evening News and could not be reached for comment.

Rather, who is currently one of four anchors on the top-rated "60 Minutes" said yesterday that he just hasn't "anything to say at this time" about the reports of major offers made to him by ABC, CBS and ABC.