MOSCOW — Negotiators meeting in Minsk, Belarus, reached a tentative deal for a cease-fire in Ukraine on Tuesday night, setting the stage for a meeting of the leaders of Russia, Ukraine, Germany and France to sign the agreement on Wednesday, according to media reports.

The initial reports came from Tass, a Russian government-connected news service, and BelTa, a Belorussian news agency. However, in a report on its website, a Ukrainian weekly newspaper, Zerkalo Nedeli, disputed the report of a deal.

Citing its own unnamed source, the newspaper said that Tass was trying to bolster the proposals put forward by the Russian-backed separatists who are battling the Ukrainian government.

Russia’s Interfax news agency also said reports of a deal were premature, as did representatives of the contact group working on an agreement, Reuters reported.