Italy was outraged by the acquittal by a military jury of Capt. Richard Ashby, the Marine pilot charged with causing the accident when his jet clipped a ski gondola cable in the Italian Alps last year.
Mr. Clinton said Americans were "profoundly regretful and apologetic" about the cable car accident. He said that military advisers would review operational and safety measures at U.S. bases in the area to ensure that future tragedies can be prevented.
"We are horrified and heartbroken by what happened and we will do our best to make sure something like that doesn't happen again," Mr. Clinton said.
D'Alema echoed the president's sentiments, expressing his trust in the efforts of the military to uncover the truth.
"It is up to the justice system to determine who is responsible and who is guilty," D'Alema said.
"I appreciated President Clinton's words very much and the commitments he's takenÂ…we shall say we are satisfied when whoever is responsible for what happened is found guilty and punished," he added.
Neither Mr. Clinton nor the prime minister wanted to comment in detail on the pending case.
On Thursday, D'Alema had said he was baffled by the verdict. The meeting between the two leaders had been set up long ago, and it was mere coincidence that it came on the heels of the acquittal. D'Alema said Thursday that Italy will explore its options for pursuing a case.
Meanwhile, the acquitted Marine said Friday he would like to hug the relatives of the victims if they'd let him.
"I don't know if they would. I don't know how to put it into words," said Capt. Richard Ashby.
Ashby's offer got a chilly response from Sindy Renkewitz, 20, a German whose father and sister were killed. Other relatives who attended Ashby's trial were returning home Friday and couldn't be reached for comment.
"I just want to ask him if he can go on and live his life as normal as before. I think I really need to do that," Renkewitz said. "I cannot say what kind of apology I expect."
Ashby, 31, also said he and his three crewmates wrote the families a sympathy letter the day after the accident, but the Marines refused to deliver it. A public affairs officer told the aviators, "We represent the Marine Corps, not you," Ashby said.
The letter said: "What occurred on 3 February was a tragedy. We cherish life and take our jobs very seriously. We would never do anything to purposefully endanger the lives of others. We all share in your tremendous loss."
A jury of eight Marine officers acquitted Ashby of 20 counts of involuntary manslaughter and other charges in the Feb. 3, 1998, disaster near Cavaese, Italy.
Prosecutors said Ashby ignored altitude and speed limits, while his attorneys said that an alarm never warned Ashby he was flying too low and that an optical illusion made him think he was flying higher.
The verdict enraged and embittered relatives of the victims -- all of them Europeans -- as well as Italian leaders.
Ashby said his life isn't the same. "I don't know if there isn't a single aspect of my life that hasn't changed from this whole thing. That's when we come into the recovery phase," the aviator said.
Once destined for a job flying the swifter F-18 fighter jets, Ashby said he doesn't know whether he will stay in the Marine Corps.
Ashby and his navigator, Capt. Joseph Schweitzer, 31, of Westbury, N.Y., face obstruction of justice charges over a missing videotape Schweitzer shot during the flight. They could get a year in prison if convicted.
Schweitzer also is scheduled to stand trial March 22 on the same charges Ashby faced.