YEREVAN (RFE/RL)-The Russian and Armenian governments have finalized a far-reaching agreement that will prolong and upgrade Russian military presence in Armenia, a diplomatic source in Yerevan said on Friday.

The source told RFE/RL's Armenian service that the two governments have worked out corresponding amendments to a 1995 treaty regulating the presence of a Russian military base in the country. They are likely to be signed during Russian President Dmitry Medvedev's visit to Armenia next week, he said.

The amendments will extend Russia's basing rights by 24 years, to 2044, and upgrade the mission of its troops headquartered in Gyumri. The Interfax news agency reported on July 30 that a relevant "protocol" submitted to Medvedev by the Russian government makes clear that the troops will have not only "functions stemming from the interests of the Russian Federation," but also "protect Armenia's security together with Armenian Army units." It also commits Russia to supplying its regional ally with "modern and compatible weaponry and special military hardware."

Armenian Revolutionary Federation Political Affairs Director Giro said on Friday that the changes will be "worrisome" as long as the Armenian government has not convincingly explained their rationale.

"My impression is that Russia has found an opportune moment to clinch from Armenia an extension of its basing rights in return for satisfying some of Armenia's demands," Manoyan told a news conference.