MOSCOW -- Russian President Vladimir Putin hosted the leaders of Armenia and Azerbaijan on Monday to try to broker a settlement to a longstanding conflict between the two ex-Soviet neighbours, but announced no breakthrough.

The peace talks took place as Putin鈥檚 military delivered a new missile barrage targeting Ukraine鈥檚 critical infrastructure in the conflict that has entered its ninth month.

After meetings with Armenian Prime Minister Nikol Pashinyan and Azerbaijani President Ilham Aliyev in the Black Sea resort city of Sochi, Putin said they had to remove continuing points of disagreement from a prepared statement that was to have formed the basis of a peace deal. He called the meetings 鈥渧ery useful鈥 but declined to answer a reporter's question about the remaining sticking points, saying they were too delicate to discuss publicly.

Before the meeting with Pashinyan, Putin had said the goals would be to ensure peace and stability, and unblock transportation infrastructure to help Armenia's economic and social development.

A joint statement released after the talks said the two sides pledged to refrain from the use of force, to negotiate issues based on respect for each other's sovereignty, territorial integrity and inviolability of borders. It said Armenia and Azerbaijan would work to normalize relations, foster peace and stability, as well as the security and economic development of their region.

Armenia and Azerbaijan have been locked in a decades-old conflict over Nagorno-Karabakh, which is part of Azerbaijan but has been under the control of ethnic Armenian forces backed by Armenia since a separatist war there ended in 1994.

鈥淲e see the approaches of our colleagues to what is happening on the Armenian-Azerbaijani border and around Karabakh," Putin said Monday. "This conflict has been going on for a decade, so we still need to end it.鈥

The meetings concern implementation of a 2020 peace deal that Russia brokered. During a six-week war in 2020, Azerbaijan reclaimed broad swaths of Nagorno-Karabakh and adjacent territories that Armenian forces held for decades. More than 6,700 people died in the fighting. Moscow deployed about 2,000 troops to the region to serve as peacekeepers.

Pashinyan said Monday that he would press for Azerbaijan to withdraw its troops from the Russian peacekeeping zone in Nagorno-Karabakh, and seek freedom for Armenian prisoners of war. An extension of the Russian peacekeeping mandate was also under discussion, Russian state news agencies reported. Putin told reporters afterward that extension of Russia's peacekeeping mission would depend on resolution of other issues.

A new round of hostilities erupted in September, when more than 200 troops were killed on both sides. Armenia and Azerbaijan traded blame for triggering the fighting.

Russia is Armenia鈥檚 top ally and sponsor. In a delicate balancing act, it maintains a military base in Armenia but also has developed warm ties with Azerbaijan.

In an apparent reflection of tensions with Armenia's leadership, Putin noted last Thursday that the Kremlin had advised Pashinyan鈥檚 government before the 2020 hostilities to agree to a compromise in which Armenian forces would give up Azerbaijani lands outside Nagorno-Karabakh that they seized in the early 1990s. Putin lamented that "the Armenian leadership has taken a different path.鈥

During the 2020 fighting, Azerbaijan reclaimed not only those territories but significant chunks of Nagorno-Karabakh proper.