The leaders of Armenia and Azerbaijan will hold talks in Brussels on Sunday, the European Union said, amid efforts to reach a peace deal over their three-decade territorial dispute.

European Council president Charles Michel will host Armenia's Nikol Pashinyan and Azerbaijan's Ilham Aliyev as part of the push "to promote stability in the South Caucasus and normalisation between the two countries", a statement said Monday.

The meeting in Brussels comes after the United States said "tangible progress" was made towards a peace agreement to end the dispute over the enclave of Nagorno-Karabakh at talks between their foreign ministers in Washington last week.

The EU statement said the two leaders had also agreed to meet together with the leaders of France and Germany on the sidelines of a European summit in Moldova on June 1.

They in addition committed to meeting in Brussels "as frequently as necessary to address ongoing developments on the ground", the statement said.

Armenia and Azerbaijan were both republics of the Soviet Union and gained their independence when it broke up in 1991.

The two sides have gone to war twice over disputed territories, mainly Nagorno-Karabakh, a majority-Armenian enclave inside Azerbaijan.

Tens of thousands were killed in the wars, one lasting six years and ending in 1994, and the second in 2020, which ended in a Russia-negotiated ceasefire deal.

But clashes have broken out regularly since then.

Azerbaijan has injected new tensions by placing a checkpoint on the Lachin Corridor, the only land link between Armenia and Nagorno-Karabakh.

Armenia views the move as a violation of a ceasefire negotiated between the two sides.

The Western mediation efforts come as major regional power Moscow has struggled to maintain its decisive influence due to the fallout from its war on Ukraine.

The Kremlin has insisted there is "no alternative" to the ceasefire deal it signed with the two warring neighbours in 2020 that saw Russian peacekeepers deployed on the ground.