President Boris Yeltsin appointed a former KGB officer and loyal ally as head of Russia's counterintelligence service Monday, in what his spokesman said could herald a shake-up of state security.


Presidential spokesman Sergei Medvedev said Colonel General Mikhail Barsukov, until now responsible for guarding Kremlin leaders other than the president, would replace Sergei Stepashin as director of the Federal Security Service, or FSB.


Medvedev hinted that further changes were on the way at the FSB, the successor to the feared KGB, which was dissolved in 1991.


"The naming of Barsukov as director of the state security service does not exclude personnel changes connected with the reorganization of all security-service systems," Medvedev told Ekho Moskvy radio station in an interview. He gave no details.


Yeltsin later introduced Barsukov to senior officials of the FSB, whom he called to a meeting in the sanatorium where he is recovering from a minor heart attack two weeks ago, Interfax said.


Addressing the meeting, Yeltsin urged the FSB officials to step up their energies and effectiveness to ensure the security of the state and its citizens.


The appointment of Barsukov, 47, was part of a reshuffle in which Stepashin and the interior and nationalities ministers were sacked June 30 for mishandling a hostage-taking raid by Chechen gunmen on the southern town of Budyonnovsk last month.


Yeltsin quickly chose new nationalities and interior ministers.


But he took longer to name A trained ex-KGB operative, Barsukov has been working from the Kremlin since 1991 and has carried the title of Moscow Kremlin commandant.


Barsukov has not previously worked at the FSB. But Yeltsin also appointed an experienced FSB officer, Viktor Zorin, as first deputy director of the service, prompting speculation that Barsukov may have a mainly political role.


"An optimistic view is that Barsukov will be expected to ensure operations are loyal to the president and that Zorin will take charge of professional matters," said Alexander Konovalov, an independent military analyst.


"But I think such a move would collapse in a month. I think it is a negative appointment when a bodyguard becomes head of the intelligence service."


Several deputies at the State Duma, the lower house of parliament, were also wary of the appointment.


"I am not delighted. It is unlikely to be seen as progress compared to Stepashin because he had his own concept of reform in the service, even though he never managed to carry it out," said Sergei Yushenkov, head of the Duma's defense committee.