UNITED NATIONS - UN Secretary-General Ban Ki-moon on Wednesday deplored elections planned by rebel groups in eastern Ukraine, saying the vote will seriously undermine the Minsk Protocol and Memorandum.

"The Secretary-General deplores the planned holding by armed rebel groups in eastern Ukraine of their own 'elections' on Nov 2, in breach of the constitution and national law," Ban's spokesman Stephane Dujarric said in a statement.

He said that these "elections" will seriously undermine the Minsk Protocol and follow-up memorandum, which were signed by the Ukrainian government and opposition groups in the Belarussian capital in September to seek a ceasefire in the east of the country. The Minsk peace accords "need to be urgently implemented in full," he said.

The UN chief urged all to uphold the agreements and work toward a peaceful resolution of the conflict and reiterated the fundamental importance of restoring stability and safeguarding the sovereignty and territorial integrity of Ukraine, the statement said.

Last month, leaders of the self-proclaimed "Donetsk People's Republic" and "Lugansk People's Republic" announced plans to hold elections on Sunday to elect regional leaders and legislative bodies.

The Ukrainian Foreign Ministry on Tuesday denounced the elections, calling them "illegitimate".