BAGHDAD, March 10 (Reuters) - U.S. and Iranian delegates to an Iraqi peace conference in Baghdad on Saturday discussed their relations in Iraq, but nowhere else, Iraqi Foreign Minister Hoshiyar Zebari said. "It was a lively exchange, not only with them (the Iranians) but the Syrians also," Zebari said at a news conference reporting on the one-day meeting of regional and world powers aimed at promoting peace in Iraq. Iraq called the meeting to enlist support to end violence four years after the U.S. invasion but it was also a rare opportunity for officials from Washington and Tehran to meet at a time of growing tension over Iran's nuclear ambitions. "(There were) exchanges regarding relations between the two in Iraq, not anwhere else. That's why they were very constructive," Zebari said of the U.S.-Iranian interaction at the multilateral talks.