Armenian PM Pashinyan has called the deal a ‘milestone’ on the road to peace between the rivals, but protesters accuse him of betrayal.

Armenia has returned four border villages to Azerbaijan, a key step towards normalising ties between the historic rivals who have fought two wars since the collapse of the Soviet Union.

Armenia’s security service said on Friday that its border guards had “officially” taken up new positions reflecting a border delimitation agreement between the two countries, handing back the villages of Baghanis, Voskepar, Kirants and Berkaber.

Confirming the handover, Azerbaijan’s Deputy Prime Minister Shahin Mustafayev meanwhile announced that his country’s border guards had taken control of the four settlements, which Azeris know as Baghanis Ayrum, Asagi Eskipara, Heyrimli and Kizilhacili.

Armenian Prime Minister Nikol Pashinyan had agreed to the move in March as part of efforts to secure a lasting peace agreement between the countries. On May 16, Yerevan and Baku redrew 12.7km (8 miles) of borderland, reflecting the return of the four uninhabited villages that were seized in the 1990s by Armenia.

Pashinyan last week described the deal as a “very important milestone for further strengthening Armenia’s sovereignty and independence”.

However, Armenian residents of nearby settlements say the transfer could cut them off from the rest of the country and accuse Pashinyan of unilaterally giving away territory without any guarantees in return.

The premier’s move has set off weeks of antigovernment protests in Armenia, with thousands of demonstrators led by charismatic Archbishop Bagrat Galstanyan accusing him of betrayal and demanding his resignation.

While the settlements are deserted, they are considered strategically important since they are located close to Armenia’s main highway north towards the border with Georgia. Much of Armenia’s trade travels on this road, and it goes to the pipeline through which it receives gas from Russia.

Peace deal

Azerbaijan had been demanding the return of the villages as a condition for a peace deal after more than three decades of conflict, mostly centred on the region of Nagorno-Karabakh.

Momentum shifted dramatically in favour of Azerbaijan last September when its forces staged a lightning offensive to regain control of Nagorno-Karabakh, where ethnic Armenians had enjoyed de facto independence since the mid-1990s.

Virtually the entire population of 100,000 people fled to Armenia within days.

The episode was a heavy blow to Yerevan, but it also removed a long-running source of disagreement from the table, paving the way for a deal that has been so far elusive.

Azerbaijan and Armenia still have other unresolved territorial disputes though, mostly focused on enclaves, with both sides demanding the other party relinquish control or provide access to them.