"The manoeuvres scheduled to start on Friday will involve armoured units as well as artillery, drones and military helicopters," the army's ground forces commander General Kioumars Heydari told the official IRNA news agency.

Heydari said they were "combat readiness exercises for the ground forces in this region," but gave no details of where they would be held or how long they would last.

Azerbaijani President Ilham Aliyev had criticised Tehran over the drills, calling them "a very surprising event".

"Every country can carry out any military drill on its own territory. It's their sovereign right. But why now, and why on our border?" he said in an interview with Turkish news agency Anadolu published on Monday.

His comments were quickly rebuffed by Iran's foreign ministry spokesman Saeed Khatibzadeh.

"The drills carried out by our country in the northwest border areas... are a question of sovereignty," Khatibzadeh said in a statement on the ministry website.

He also took a dig at Azerbaijan's close relations with Iran's arch foe Israel. "Iran will not tolerate the presence of the Zionist regime near our borders," he said.

A major supplier of arms to Azerbaijan, Israel came under diplomatic fire from Armenia during last year's conflict between the Caucasus neighbours.

Iran and Azerbaijan share a border of around 700 kilometres (430 miles).

Ethnic Azeris make up around 10 million of Iran's 83 million people.