Iran will help push militants out of the last Syrian rebel stronghold with "the least human cost", Foreign Minister Mohammad Javad Zarif said on Tuesday.
"We will try to prevent any damage to the Syrian people and complete the process of clearing extremists," Zarif said, according to state news agency IRNA.
"The situation in Idlib is sensitive. We will try to remove terrorists from Idlib with the least human cost," he added.
Iran has been a key backer of Syrian President Bashar al-Assad in the seven-year conflict, and will assist the push against the last rebel stronghold along the Turkish border.
Zarif said the looming offensive had been discussed with Turkey and Syria.
It will also be addressed at Friday's summit in Tehran between the presidents of Iran, Turkey and Russia.
US President Donald Trump warned Syria, Iran and Russia on Monday against attacking the province, saying the offensive may cause a "human tragedy".