Ukraine is ready for dialogue but will not bow to "blackmail" by pro-Russia rebels.

Ukrainian Acting President Oleksandr Turchynov said during the roundtable talks in Kyiv May 14.

The talks were attended by former leaders, government officials, and lawmakers -- but not pro-Russian separatists waging an armed insurgency in the east.

The OSCE has welcomed the launch of Ukraine's first national dialogue on constitutional reform and the crisis in the country's east, Interfax reports.

Swiss Foreign Minister Didier Burkhalter, who is the OSCE's chairman in office, said the roundtable "allowed for constructive and engaged discussions and set the tone for the following editions to take place in the regions."

He also expressed hope that an "inclusive national dialogue" would help stabilize the political situation ahead of a presidential election set for May 25.