The command staff of the Collective CIS Peacekeeping Force had earlier said the rotation would be over on May 30.
The Peacekeeping Force Headquarters said that 500 Russian troops would be replaced in line with a May 1994 ceasefire agreement and a mandate on peacekeeping operations in the conflict zone.
Abkhazia is one of Georgia's two breakaway de facto independent republics, along with South Ossetia, which broke away from Georgia following the collapse of the Soviet Union.
Russian peacekeepers have been deployed in the republics since the 1990s. Moscow recently bolstered the number of its peacekeepers in Abkhazia in response to a Georgian troop build-up, but said the increase was still within previously agreed limits of 3,000 soldiers.
Relations between Moscow and Tbilisi have drastically deteriorated since Russia's former president Vladimir Putin called for closer ties between Moscow and the two breakaway republics in mid-April.
Georgia has accused Russia of trying to annex Abkhazia and South Ossetia, while Moscow says Tbilisi is planning to invade Abkhazia.
