Hopes have risen for a breakthrough in the stalled EU enlargement process in the Western Balkans after Bulgaria’s opposition agreed to back lifting the country’s veto on the start of accession talks with Macedonia North.

Boïko Borissov, former Bulgarian Prime Minister, declared that his centre-right party GERB would vote in favor of the opening of negotiations with the EU. If passed by the Bulgarian parliament, it would also unblock accession talks with Albania ahead of a summit of EU leaders on Thursday and Friday.

“This is the most correct decision for the future of the Balkans, the EU and Bulgaria,” Borisov said. “We will not stay on the dark side of Eurasia, we will not allow poutinization.”

The move marks a turnaround for Borisov, who stalled talks with North Macedonia in 2019 in a dispute over the former Yugoslav country’s interpretation of Balkan history.

Kiril Petkov, Bulgaria’s reformist prime minister, was on the verge of striking a deal with Skopje unblocking talks when one of his coalition parties pulled out in protest at the issue earlier this month, leaving him clinging to power .

A vote on the enlargement talks could take place in parliament on Thursday, with GERB’s backing sufficient to lift Sofia’s veto.

European officials fear that blocking EU enlargement could create political instability in the Western Balkans and disillusionment with the Western orientation of the region, which could be exploited by Russia.

In another sign of possible movement, North Macedonia, Serbia and Albania confirmed on Wednesday that they would attend a summit in Brussels tomorrow with EU leaders, a day after threatening not to attend the meeting on Bulgaria’s opposition to North Macedonia’s candidacy.

“We will attend the EU Council meeting,” Albanian Prime Minister Edi Rama said, adding that Bulgaria’s position amounted to “abduction” and “destroyed” the spirit of Europe “.