(Reuters) - Ukraine's foreign ministry summoned Slovakia's ambassador in Kyiv on Thursday to reject accusations that it is meddling in its neighbour's internal affairs and to accuse Slovak Prime Minister Robert Fico of being a "mouthpiece" for Russia.

Relations between Robert Fico in Bratislava and Volodymyr Zelenskyy in Kyiv have become increasingly bitter over the month.

A diplomatic rift between Bratislava and Kiev has deepened over Ukraine's decision to cut off the transit of Russian gas through Slovakia and mutual accusations regarding energy policies. The Slovak Foreign Ministry said on Wednesday it summoned Ukrainian ambassador Myroslav Kastran to convey a "strong protest over statements made by Ukrainian officials.