BRUSSELS (Reuters) - European Union ambassadors agreed on Friday formally to start accession negotiations with Ukraine and Moldova, the Belgian EU presidency said, adding this would take place at intergovernmental conferences on June 25.

Belgium, which holds the six-month rotating presidency of the EU, said on social media post X that the decision should be officially cleared by finance and economy ministers meeting next Friday.

Opening talks with the European Union would be a morale boost for Ukraine as Russia's forces are advancing in the Donetsk region and opening a new front in the northeastern region of Kharkiv.

The agreement means that Hungary has dropped for now its opposition to Ukraine's graduation to EU membership. Budapest, which has close ties to Moscow, has said it has doubts about European Commission's assessment that Ukraine is ready.

The Commission said a week ago that both countries met all the criteria for accession negotiations formally to begin.

The 27 EU members have to agree unanimously agree to start the negotiations, which take years to conclude.

Belgium and the Commission had been keen to get agreement before Hungary takes over the rotating presidency from July 1 for six months.

Kyiv applied for EU membership in the weeks after Russia launched its full-scale invasion in February 2022 and it was granted candidate status four months later.

(Reporting by Philip Blenkinsop; Editing by Alistair Bell)