UN Secretary General Ban Ki-moon on Wednesday has said he backs a thorough compliance with the Minsk Protocol reached between the conflict parties in Ukraine.

"I'm urging again that the parties should sit down together to abide by, fully, the letters and spirit of the Minsk Protocol and Memorandum," Ban said.

Answering questions following his end-of-year briefing at UN Headquarters in New York, Ban told journalists that the "continuing, negative" situation in Ukraine had been "a source of deep concern for the whole international community."