An important round of peace talks between the government of Ukraine and pro-Russian separatist rebels, which was due to take place in Minsk on Friday, has been called off, Belarusian officials reportedly announced.

"There will be no negotiations of the Contact Group this Friday in Minsk," ministry spokesman Dmitry Mironchik was quoted as saying by local news agencies. There is no word on whether they will be rescheduled. In addition to the government of Ukraine and the rebels, the Ukraine Contact Group are also party to the negotiations, which includes representatives of Russia and the Organization for Security and Cooperation in Europe.

Representatives from the warring sides held a first round of talks in the Belarusian capital on Wednesday, where they agreed to a prisoner swap, according to the Deutsche Presse-Agentur news agency. The talks scheduled for Friday were expected to cover issues including the withdrawal of heavy weapons from the front line, and ending Ukraine's economic blockade of rebel-held areas, according to a BBC report

Ukraine agreed to a ceasefire with rebel groups in September, but fighting has continued regardless. The United Nations released an estimate on Dec. 15, which suggested that about 1,300 people have been killed in the strife-torn region since the ceasefire was put in place. 

In advance of the talks, central European leaders had stressed the importance of the negotiations. “Russia must change its policy,” Polish Foreign Minister Grzegorz Schetyna said on Polish Radio earlier this week, according to Bloomberg. “It needs to take steps to ensure we solve problems at the negotiating table and not in the trenches.”

In addition, French President Francois Hollande stressed the “urgent” need to achieve progress in implementing the ceasefire agreements.