More than 100,000 refugees have arrived in Armenia from Nagorno-Karabakh, Yerevan and the head of the UN refugee agency UNHCR have said. 

Azerbaijan had earlier this month launched an offensive to gain control of the region, prompting thousands of ethnic Armenians to flee in fear of persecution. 

"Many are hungry, exhausted and need immediate assistance," UNHCR chief Filippo Grandi said on social media.

"UNHCR and other humanitarian partners are stepping up their support to the Armenian authorities, but international help is very urgently required," Grandi added.

The Armenian government on Saturday put the exact figure at 100,417, out of Nagorno-Karabakh's estimated population of 120,000.

Artak Beglaryan, a former official from Nagorno-Karabakh's separatist government, said that "the last groups" of residents from the enclave were heading to Armenia on Saturday.      

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

Armenia accuses Azerbaijan of 'ethnic cleansing'

Armenia has accused Azerbaijan of carrying our a campaign of "ethnic cleansing" against the majority Armenian population of Nagorno-Karabakh. 

Baku, however, denies the claim, and has urged ethnic Armenians of the enclave to "reintegrate" into Azerbaijan. 

Yerevan has called on the International Court of Justice (ICJ), the UN's highest court, to protect Nagorno-Karabakh's inhabitants and ensure that Baku doesn't move to displace the remaining Armenians. 

A UN mission is expected to reach Nagorno-Karabakh this weekend to assess humanitarian needs there, marking the first time an international body gained access to the region in around three decades. 

fb/dj (AFP, AP, dpa. Reuters)