Turkey has announced plans to hold joint military exercises with Azerbaijan near the Iranian border as tensions between Baku and Tehran continue to rise.

“The Steadfast Brotherhood 2021 drill will take place with the participation of Turkey and Azerbaijan in Nakhchivan, Azerbaijan between 5 and 8 October,” said Major Pinar Kara, spokesperson for Turkey’s Ministry of National Defense.

The announcement comes on the heels of widescale military exercises Iran launched near its northwestern border last week, a move that was heavily criticized by the Azerbaijani President.

On 27 September, Azerbaijani President Ilham Aliyev said he was “very surprised” by Iran’s decision to hold military drills close to their border, asking: “Why now and why near our borders?”

In response to these comments, Iran fired back saying the drills seek to secure the country’s territorial security following reports that Baku is hoping to finalize a $2 billion arms deal with Israel.

“Iran will not tolerate the presence of Zionist forces near its borders,” Iranian Foreign Ministry spokesman Saeed Khatibzadeh said last week, adding that the country will take any action deemed necessary to protect its national security.

Azerbaijan is a major exporter of oil to Israel, which, in turn, supplies the South Caucasus nation with drones and other high-tech weaponry. This arrangement gave Baku the edge last year during a 40-day war against Armenia.

The joint military drills by Azerbaijan and Turkey will begin one day after the Armenian Foreign Minister’s visit to Tehran, during which the two nations agreed to deepen economic cooperation.