Russian President Vladimir Putin will visit Iran on Tuesday in just his second foreign trip since he launched the invasion of Ukraine in February.

Mr Putin will meet Iranian Supreme Leader Ayatollah Ali Khamenei and Turkish President Recep Tayyip Erdogan.

Grain exports, Syria and Ukraine will be discussed in Tehran, a Turkish official said.

The Russian leader has limited his international visits to former Soviet states since war broke out in Ukraine.

In June, Mr Putin made his first international trip since February when he visited Tajikistan and Turkmenistan, both former members of the USSR now led by authoritarian rulers and Russian allies.

Tuesday's visit will offer Mr Putin the opportunity to deepen ties with Iran, one of Moscow's few remaining international allies and a fellow target of Western economic sanctions.

It follows allegations by US officials last week that Tehran was planning to supply Russia with hundreds of drones for its war in Ukraine. And on Tuesday, the Russian energy giant Gazprom signed a new development deal worth $40m (£33m) with Iran's state oil company.

"The contact with Khamenei is very important," Yuri Ushakov, Mr Putin's top foreign policy adviser, told a media briefing on Monday. "A trusting dialogue has developed between them on the most important issues on the bilateral and international agenda."