Azerbaijan's President Ilham Aliyev thanked his Turkish counterpart Recep Tayyip Erdoğan Monday for support against Armenia's border violations in the occupied Nagorno-Karabakh region.

Hikmet Hajiyev, assistant to the president and foreign policy chief for Azerbaijan's Presidency, said Baku welcomed Erdoğan's remarks calling on Armenia to immediately end the occupation of Azerbaijani territories.

Turkey, especially President Erdoğan, has strongly condemned the attack and shown absolute support, Hajiyev said.

Azerbaijan always stands by Turkey based on the "two states, one nation" principle, he quoted Aliyev as saying.

As soon as the violations began, Ankara reiterated its support to Azerbaijan, with many officials, mainstream parties and the Turkish Foreign Ministry declaring unwavering backing to its brotherly Turkic nation.

In a statement released Sunday, the Turkish Foreign Ministry said Armenia is staging yet another provocation.

"We condemn in the strongest terms the Armenian attack which is a blatant violation of international law and has caused civilian casualties. With these attacks, Armenia has shown once again that it is the biggest obstacle on the road to peace and stability in the region," it added.

"Azerbaijan will of course use its legitimate right of self-defense to protect its civilians and territorial integrity. In this process, Turkey's support for Azerbaijan is unwavering. However, if Azerbaijan wants us to support them, we will do so," Turkish Foreign Ministry spokesperson Hami Aksoy said in the statement.

Turkish Defense Minister Hulusi Akar also condemned Armenia's "heinous" attack in a statement released later Sunday. "We are with our Azerbaijani brothers, who are fighting for their territorial integrity, to the end with all the means we have," he said.

"The occupier, Armenia, attacked Azerbaijan and showed that it is trying to stage a provocation with this violation of the cease-fire. Armenia's aggressive attitude is the biggest obstacle to peace and stability in the Caucasus. Armenia should immediately halt this aggression, which will add fire to the tensions in the region," Akar added.

Other politicians, Parliamentary Speaker Mustafa Şentop and the chairperson of the main opposition Republican People's Party (CHP), Kemal Kılıçdaroğlu, also issued statements condemning Armenia's aggression.

"Armenia is an incorrigible terrorist state threatening peace," Şentop said, while Kılıçdaroğlu asserted that his party condemns "Armenian aggression, threats to regional peace."

Good Party (IP) Chairwoman Meral Akşener also condemned the Armenian aggression, saying that the IP fully stands with Azerbaijan.

In a statement on Twitter, Akşener said the Armenian attacks against Azerbaijan are unacceptable.

"I call on the government, the international community and the Minsk Group to end the Armenian occupation and take steps to immediately solve the matter," Akşener said.

Nationalist Movement Party (MHP) Chairman Devlet Bahçeli condemned the Armenian aggression and highlighted that Karabakh belongs to Azerbaijanis.

"Karabakh belongs to the Turks. It is a Turkish homeland. Nobody will change this firm and exceptional truth. We stand with Azerbaijan with our blood, lives and presence," Bahçeli said in a statement.

Diplomatic relations between Turkey and Azerbaijan have always been strong as both nations share a similar history, language and heritage.

Often called "one nation and two states" by both sides' leaders, the countries continue to enjoy tremendous progress in ties.

The Azerbaijan Democratic Republic was founded on May 28, 1918, as the first secular democratic state in the Muslim East. Its founder was Mammad Amin Rasulzadeh, and the first state to officially recognize the republic was the Ottoman Empire, the predecessor of modern Turkey.

Azerbaijan proclaimed its independence from the Russian Empire in 1918 but only managed to operate for 23 months before being invaded by the Soviet Union. The modern Republic of Azerbaijan declared its independence on Aug. 30, 1991, shortly before the Soviet Union disintegrated.

Border clashes broke out early Sunday when Armenian forces targeted Azerbaijani civilian settlements and military positions, leading to casualties.

Relations between the two former Soviet nations have been tense since 1991 when the Armenian military occupied Nagorno-Karabakh, an internationally recognized territory of Azerbaijan.

Four United Nations Security Council and two U.N. General Assembly resolutions demand the withdrawal of the occupying forces.

The OSCE Minsk Group – co-chaired by France, Russia and the U.S. – was formed in 1992 to find a peaceful solution to the conflict, but to no avail. A cease-fire, however, was agreed upon in 1994.

The European Union, Russia and NATO, among others, have urged an immediate halt to clashes along the frontier.