BAGHDAD, Iraq — Prospects for another round of talks between Iranian and American officials soon appeared dead yesterday after Iraq’s foreign minister said tensions between Tehran and Washington made such a meeting impossible.

Foreign Minister Hoshyar Zebari’s comments showed how sharply American-Iranian relations over the issue of Iraqi violence, which had appeared to improve last fall, have fallen in the wake of fighting in Iraq between American-led forces and Shiite Muslim militias.

Yesterday was one of the calmest days since violence flared on March 25, but the American military reported a Marine had been killed in Anbar province on Tuesday without giving further details.

The Marine’s death was the fifth reported in the western province in a week, an unusual number in a region that had seen a dramatic drop in American deaths in the past year. The decline is attributed to the birth in Anbar of the Awakening movement, which turned tribal sheiks who once had harbored insurgents into allies with American and Iraqi forces.

Mr. Zebari’s comments came two days after the Iranian Foreign Ministry’s spokesman, Mohammed Ali Hosseini, said no talks could take place as long as American forces were involved in “open and extensive bombing” of Baghdad neighborhoods. Mr. Hosseini was referring to American strikes on Shiite militiamen in strongholds of Shiite cleric Muqtada al-Sadr and his Mahdi Army.

Mr. Zebari said Iraqi officials in recent months had proposed four possible dates for Iranian-American talks on Iraq’s security, the most recent March 6. He did not say which side balked and did not blame either side for the inability to arrange talks since the last round in August. That was the third time since March 2007 that Iranian and American officials had come together, at the Iraqi government’s urging, to discuss ways of stabilizing Iraq.

Mr. Zebari made clear that Iraq found it maddening that it is squeezed between two allies who cannot get along with each other.

“The atmosphere of … media attacks, exchange of attacks and accusations and lack of trust and confidence … I don’t think we will succeed in having the fourth round” of talks, he said.

“The idea is not dead,” Mr. Zebari added. “We hope we will be able to resume it.”

Neither Washington nor Tehran shows signs of budging in the current standoff, which escalated this month after American military officials said Iranian-made weapons manufactured in 2008 had been found in the southern city of Basra. They said the weapons showed that Iran had not kept a vow made to Iraq late last year to stop interfering in Iraq’s violence.