YEREVAN (RFE/RL) -- The U.S., Russian, and French diplomats cochairing the OSCE Minsk Group are in Baku on May 29 for talks with Azerbaijani President Ilham Aliyev.
U.S. Deputy Assistant Secretary of State Matthew Bryza, the U.S. cochair, met in Yerevan on May 28 with Armenian Foreign Minister Eduard Nalbandian.
Bryza told RFE/RL's Armenian Service that Aliyev and Armenian President Serzh Sarkisian made "significant progress" at their last meeting in Prague earlier this month and he "expects the same in St. Petersburg."
He added that "I do believe that a breakthrough can happen at St. Petersburg or shortly thereafter."
Some Azerbaijani officials have disagreed with the optimism expressed by the mediators. A top aide to Aliyev last month denounced Bryza's upbeat statements, while Azerbaijani Foreign Minister Elmar Mammadyarov has said that the two parties have not moved closer to a settlement since Sarkisian took office in April 2008.
Byrza said such criticism is normal and "each side has to follow its own tactics to try influence the other side."
The agreement proposed by the Minsk Group mediators reportedly calls for a gradual solution to the dispute that ends in a referendum of self-determination in Nagorno-Karabakh after the return of Armenian-occupied territories surrounding Karabakh to Azerbaijan.
But Aliyev said in a televised nationwide address on May 27 that "there is and there can be no mechanism for Nagorno-Karabakh's secession from Azerbaijan at the negotiating table."
He added that "Nagorno-Karabakh will not be an independent state neither today, nor in 10 or 100 years."