An Iraqi passenger plane has landed in the Iranian capital, Tehran, for the first time since the outbreak of war between the two countries 25 years ago.
Almost one million people died in Iran-Iraq conflict
Regular flights from Baghdad to Tehran are expected to begin on 16 November, an Iranian aviation official said.
The move is seen as a further sign of reconciliation between the neighbours who fought an eight-year war.
Iran's president told Iraq's visiting deputy PM that he backed Iraqi stability, Iranian media reports.
"Protection of Iraq's territorial integrity, independence and might is of special significance to Iran," state-run television quoted Mahmoud Ahmadinejad as saying after talks with Ahmed Chalabi.
The US has accused Iran of not doing enough to stop militants entering Iraq to carry out attacks and the UK has repeated claims that bomb-making technology is crossing into Iraq from Iran. Iran denies the accusations.
The plane run by the Iraqi national airline arrived at Tehran's international airport with 65 passengers including Iraqi officials, a spokesman for the Iranian civil aviation authority told Agence France Presse news agency.
But Iran would only allow its aircraft to fly to Baghdad when security issues were resolved, Reza Jafarzadeh said.
"If they give us a security guarantee we would have no problem resuming flights to Iraq," he told Reuters news agency.
During their talks, President Ahmadinejad also told Mr Chalabi that Iran was willing to offer its experience and expertise to rebuild Iraq.
He called for the acceleration of work on setting up an oil pipeline between Iran's city of Abadan and the Iraqi city of Basra.
The talks came ahead of a planned visit by Mr Chalabi to the US.
Mr Chalabi was a favourite Iraqi leader in Washington during the run-up to war. But he lost US support last year after being accused of leaking US secrets to Tehran, which he denied.
He is now scheduled to meet US officials in Washington next week, in what some see as a warming of ties.
However, correspondents say that some US officials have played down the significance of the visit - calling it a business trip related to Mr Chalabi's work with Iraq's budget and oil industry.