Syria will let U.N. investigators trying to identify the killers of former Lebanese Prime Minister Rafik al-Hariri question Syrian officials in Damascus on their own, the Syrian ambassador to London said on Friday. Chief United Nations investigator Detlev Mehlis has complained that Syrian security figures interviewed in Damascus last month appeared to give only prepared responses. The Syrians had insisted that other officials attend the interviews. "There shouldn't be a problem to meet with them as witnesses any time," the ambassador, Sami Khiyami, told Reuters. "Mehlis can meet them completely alone, even choose a place in Damascus with a U.N. flag," he said, adding that the investigators would be free to produce their witnesses at the interviews, while keeping their identities secret if necessary. The U.N. Security Council demanded last week that Syria cooperate fully with Mehlis's inquiry into the Beirut bombing that killed Hariri and 22 others or face "further action".