Senator Thomas F. Eagleton (D. Mo.) last night announced his resignation as the Democratic Vice Presidential nominee exactly a week after his surprising disclosure of previous hospitalization and psychiatric treatment for depression and nervous exhaustion.

Eagleton made the announcement in Washington at a press conference called after an hour and a half meeting with Senator George S. McGovern (D.S.D.), the Democratic Presidential nominee.

McGovern made no immediate announcement about Eagleton's replacement but said he would make such a statement tonight at 9 p.m. over nationwide television.

Eagleton's announcement heightened speculation about who McGovern's new choice would be. According to a copyrighted story in yesterday's Boston Globe, McGovern has already made his choice and has tapped Lawrence F. O'Brien, former chairman of the Democratic National Committee, to be his running mate.

The Globe said that according to several top Massachusetts Democrats the decision was final. But several other political observers did not agree with this judgement.

Boarded Together

At the funeral of the late Senator Allen E. Ellender (D. La.), McGovern left the church and boarded the senatorial bus to leave Louisiana with Senator Edward M. Kennedy (D-Mass.). It was also learned that McGovern and Kennedy sat together both on the plane to the funeral and during the service.

Both Senators refused to comment after the funeral when asked if their proximity during the day signified anything. Some observers said they thought that McGovern was making a last-ditch attempt to convince Kennedy to run as his Vice-Presidential nominee.

Rep. Edward P. Boland (D-Mass.) said in a telephone interview from Washington that he had heard nothing about O'Brien being picked to replace Eagleton. Boland, a longtime political associate of O'Brien's from their start in Springfield Democratic politics, said that he had been trying to get in touch with O'Brien all day but had been unable to reach him.

The Globe reported that Boston Mayor Kevin H. White was once again strongly considered for the spot but was discarded, again, in favor of O'Brien.

White was reportedly conferring with sides most of the day, but he got the word from Washington around noon, according to the Globe report, Aides of the mayor declined to comment.

The Globe reported that one top state Democrat said Monday "it was again a close thing for White. But we are not sure he would have taken it anyway."

'I Will Continue'

McGovern appeared with Eagleton at the press conference. "My conscience is clear and my spirits are high," Eagleton said. "This is definitely not my last press conference and Tom Eagleton is going to be around for a long, long time."

"I have consistently supported Senator Eagleton," McGovern said. "He is a talented, able United States senator whose ability will make him a prominent figure in American politicsfor many years to come."

"I am for George McGovern and I am going to continue working to see him President of the United States," Eagleton responded.

"No one could have been finer to me, more considerate, more genuinely concerned for me...than the man I'll be proud to call the next President of the United States, George McGovern," Eagleton said