The five Iranians were detained during a raid on what Tehran says was an Iranian consular building in Irbil in the autonomus Kurdish region of northern Iraq.

Hoshiyar Zebari, Iraqi foreign minister, said he hoped the visit, which lasted several hours, would lead to more talks and improve relations between Washington and Tehran.

US accusations

The US military has repeatedly accused Iranian agents of supplying Iraqi groups with weapons and training to attack US-led forces in the country.

"We hope this humanitarian gesture will help to ease tensions and facilitate further dialogue between the two countries"

Hoshiyar Zebari, Iraqi foreign minister
Earlier this week, a senior US military spokesman accused Tehran of helping to plan a raid in Karbala that led to the death of five American soldiers.

Iraq has been pressing the US and Iran to hold a second round of talks in Baghdad after a meeting in May where senior envoys from the two sides discussed the violence in Iraq.
   
"We hope this humanitarian gesture will help to ease tensions and facilitate further dialogue between the two countries," Zebari said.

"This is the first such visit since they were detained. This is a positive development."

Kazemi-Qomi and Ryan Crocker, the US ambassador, met in Baghdad on May 28 to discuss security in Iraq in what was the most high-profile meeting between the two sides in almost three decades.

The US embassy in Baghdad confirmed the meeting took place, but stressed that any diplomatic discussions between the two countries were a separate matter.
   
"The visit was a courtesy ... in response to a request from the Iranian government," Philip Reeker, embassy spokesman, said.