Outside the White House, the seat of government, protesters waved blue opposition flags and shouted "Bakiyev out!" and "Shame! Shame!" under the gaze of dozens of interior ministry troops, some deployed on the roof of the seven-storey building.
The head of the Organisation for Security and Co-operation in Europe cut short a visit to Bishkek after Bakiyev expressed concern about his meeting with opposition leader Felix Kulov.
Kulov, after talks with Miguel Angel Moratinos, the OSCE chairman-in-office, said: "We voiced our understanding that peaceful demonstrations have their right to exist."
A spokesman for Kulov declined to comment and Bakiyev's office was unavailable for a reaction.
At the height of 2005 protests, an angry mob stormed the White House, forcing Akayev to flee. Friday's protest was largely peaceful, with Kulov pledging to use only constitutional methods to bring about change.
Kulov, prime minister until December, said the protest would continue until Bakiyev met the opposition's demands.
"Our people are ready to stay here for a long time until our demands are met," he told reporters after the march.