Iranian president visits Azerbaijan as ties warm

Tensions between the two have run high for years, largely due to Baku's close ties with Iran's arch-enemy Israel and a January 2023 attack on Azerbaijan's embassy in Tehran.

Last week, Pezeshkian expressed hopes for a "rapid and serious improvement" in relations and cooperation between the two countries as part of a broader effort to "mend ties".

In a recent sign of rapprochement, Iran and Azerbaijan held two-day joint naval exercises in the Caspian Sea in November, according to Iranian media.

But Tehran has long expressed concerns that Azerbaijani territory could be used by Israel -- a major arms supplier to Baku -- to stage a potential attack on Iran.

In the January 2023 embassy attack, a gunman killed an Azerbaijani diplomat and wounded two security guards. Iran condemned the violence but attributed it to "personal" grievances.

In the aftermath, Baku shut its embassy in Tehran and both countries then ordered expulsions of the others' diplomats. But Azerbaijan's embassy reopened in the mid-2024, after Iran had sentenced the attacker to death in late 2023.

Another point of dispute between the two countries has been the so-called Zangezur corridor, a proposed direct land link between Azerbaijan and Tehran's historic rival Turkey.

Tehran vehemently opposes the project, which would run along Iran's border with Armenia.

Tehran has historically been wary of separatist sentiment among its ethnic Azerbaijani minority, which numbers around 10 million of Iran’s 83 million citizens.