Yerevan says almost the entire population of ethnic Armenians have fled Nagorno-Karabakh since Azerbaijan managed to reclaim full control of the region last week.

Nazeli Baghdasaryan, a spokeswoman for Armenia's prime minister, said Saturday that the number of refugees entering the country over the past week had reached 100,417, out of Nagorno-Karabakh's estimated population of 120,000.

The United Nations refugee agency (UNHCR) also said that 100,000 people had fled the region. It said many of those fleeing "are hungry, exhausted, and need immediate assistance.”

"At most a few hundred persons remain, most of whom are officials, emergency services employees, volunteers, some persons with special needs," Artak Beglaryan, a former separatist official, wrote on social media.

Nagorno-Karabakh is a landlocked region in the Caucasus and lies within Azerbaijan’s borders.

The region has always been internationally recognized as part of Azerbaijan though it is mostly populated by ethnic Armenians, who have resisted Azerbaijan’s sovereignty over the territory.

Last week, Azerbaijan launched an operation designed to seize control of the breakaway territory and perhaps end a three-decade-old conflict.

The operation ended on September 20, after the Azerbaijani military routed Armenian forces in 24 hours and made the separatists agree to lay down weapons, under a Russian-mediated ceasefire.

Azerbaijan’s president Ilham Aliyev said at the time that his government “began sending humanitarian aid to Azerbaijan’s Karabakh region. Fuel, foodstuffs, medicines were sent.”

Yerevan, however, accused Baku of conducting a campaign of "ethnic cleansing" to clear Nagorno-Karabakh of its Armenian population.

Baku has denied the claim and has publicly called on the Armenian residents of the territory to stay and "reintegrate" into Azerbaijan. 

On Thursday, the separatist region’s leader Samvel Shakhramanyan agreed to dissolve the government by the end of the year and become a full part of Azerbaijan. The decision marked the end of a 30-year struggle for independence from Baku.

Shakhramanyan said in his decree that “all state institutions and organizations under their departmental subordination by January 1, and the Republic of Nagorno Karabkah (Artsakh) ceases to exist.”

Residents were instructed to “familiarize themselves with the contusion of reintegration presented by the Republic of Azerbaijan,” it added.

Baku is now holding "re-integration" talks with separatist leaders.