Presidentelect George Bush announced Monday that White House spokesman Marlin Fitzwater would remain in his post in the new administration. Bush said he selected Fitzwater because "I think he's the best."

Fitzwater's appointment marked the latest in a series of high-level holdovers from the old administration to the new. But Bush promised fresh faces for his turn in the Oval Office, telling reporters, "Stay tuned for the changes."Fitzwater, a stocky, balding career government spokesman - who worked for Bush before becoming President Reagan's spokesman - said the incoming president would hold news conferences "as much as possible. They should be as regular as possible."

Bush announced the selection in an appearance in the White House briefing room from the podium where Fitzwater stands daily to answer questions about Reagan administration policy, personnel and controversies.

The president-elect said he had no other announcements, despite speculation that he soon would appoint former Sen. John Tower as defense secretary and name longtime associate Robert Mosbacher to head the Commerce Department.

Fitzwater, who celebrated his 46th birthday on Thanksgiving Day, became chief White House spokesman Jan. 12, 1987, taking over for Larry Speakes. He officially remained a deputy, however, to injured press secretary James Brady, who kept that title despite being crippled in the 1981 assassination attempt on Reagan.

Sheila Tate, Bush's press secretary during the transition period, will remain in that job until Jan. 20, Fitzwater said. Tate took herself out of the running for press secretary.

When reporters bombarded Fitzwater with questions, he joked: "A two minute honeymoon. Amazing."