Baghdad, Iraq Washington is sending a veteran Middle East hand. Tehran's envoy is a British-educated diplomat considered one of Iran's leading Western analysts.
Combine that with a flexible agenda and a matchmaking Iraqi host - and the international gathering today to help steer Iraq's future also appears as a prime opportunity for some ice-breaking overtures between Iran and the United States.
But any outreach - no matter how limited - would be shadowed by deep suspicions and grievances from both sides in their odd-couple roles: old foes yet also Iraq's two most influential allies.
"Don't expect any miracles," said Hamid Reza Jalaipour, a professor of political affairs at Tehran University.
In fact, expectations have been kept very modest before the conference, which includes delegates from Iraq's six neighbors, the five permanent U.N. Security Council members and several Arab representatives.
In Washington, the U.S. chief delegate, David Satterfield, said "we are not going to turn and walk away" if approached by Iran or Syria to discuss Iraq. But Satterfield, the top State Department adviser on Iraq, added Thursday that the United States plans to use the meeting to reinforce its accusations against both nations.
They include U.S. claims that Syria allows foreign jihadists and Sunni insurgents to cross its border into Iraq, and that weapon shipments from Iran reach Shiite militias. Both nations deny the allegations.
Iran's chief envoy, Abbas Araghchi, left Tehran without directly mentioning the United States, but said Iran "hopes to take more steps" to support the U.S.-backed government - which is led by a Shiite prime minister with close ties to Shiite heavyweight Iran.
Iran, however, has strongly denounced the U.S. military presence. The complaints grew more pointed in December after American forces detained two Iranian security agents at the compound of a major Shiite political bloc in Baghdad.
Six other Iranians were arrested Jan. 11 at an Iranian liaison office in northern Iraq. The U.S. military said they were members of Iran's elite Revolutionary Guard - a charge Tehran rejects.
The showdown over Iran's nuclear program also lurks behind any attempt to ease the nearly 28-year diplomatic freeze with Washington.
"But both Iran and the United States realize they are stuck together on Iraq," said Alireza Nourizadeh, chief researcher at the London-based Center for Arab-Iranian Studies. "So perhaps they see this meeting as a way to open some doors for bilateral talks."
For Iran, opening more direct contacts with Washington could help promote their shared interests in Iraq, including trying to stamp out Sunni-led insurgents. U.S. officials, meanwhile, need the support of Iranian-allied political groups in Iraq to keep a lid on Shiite militias.
In September, the United States joined Iran and Syria in talks on Iraq - although Washington ruled out direct talks with Iran in advance. This time, however, there is an open invitation to Iran.
And both sides have dispatched well-suited diplomats.
Satterfield has served in posts in Saudi Arabia, Tunisia, Lebanon and Syria, as well as Washington positions including the National Security Council staff. Araghchi did postgraduate studies in England and served as ambassador to Finland. He's regarded as one of Iran's leading diplomatic strategists on relations with the West.