A senior Georgian rebel commander said yesterday his forces were preparing to storm the Transcaucasian republic's parliament where President Zviad Gamsakhurdia has been under siege for more than a week.Fighting continued along Tbilisi's Rustaveli Avenue, the main thoroughfare in the capital, through the morning. But it was not clear whether rebel National Guards, backed by the shadowy Mkhedrioni (Horsemen) opposition group, had the power to force their way into the fortified complex. Rebel Guard Maj. Gela Lanchava said opposition forces had launched a successful counterattack through the city center after losing some positions to government forces fighting from their base in the parliament. Asked if they were now preparing to storm the parliament, he said: "Yes." Speaking outside rebel headquarters at the opposite end of Rustaveli Avenue from parliament, Major Lanchava said his National Guards were being backed by the Mkhedrioni, an underground opposition group which claims several thousand supporters. President Gamsakhurdia's men, who have been resisting rebel attacks for more than a week, widened their area of control after opposition military leaders had started to unite against him and called for his resignation over the weekend. A cease-fire was declared Saturday and fighting has decreased since then. But sporadic gunfire continued Sunday with each side blaming the other. The Georgian Health Ministry estimates more than 50 people have been killed and about 300 wounded in a week of conflict. Pro-Gamsakhurdia forces appeared to control most of the area around parliament. Approach roads were blocked by trucks and other barricades and a carpet of broken glass led toward the back entrance of the imposing building. The opposition accuses Gamsakhurdia of being a dictator. He denies the charges and says rebels are trying to topple a democratically elected administration. Gamsakhurdia was elected president by a landslide vote in May.