DAMASCUS (Reuters) – Syria is considering a formal U.N. request to question six Syrian officials in Lebanon in connection with the killing of former Lebanese Prime Minister Rafik al-Hariri, a Syrian official said on Monday.In Beirut, a Lebanese political source said Syrian President Bashar al-Assad’s brother-in-law Major General Assef Shawkat, head of military intelligence, is among the six.

The request by chief U.N. investigator Detlev Mehlis appeared designed to test Syria’s willingness to comply with a Security Council resolution demanding full cooperation with the probe into the February 14 assassination of Hariri."We have received a request and we are considering it," the Syrian official said, speaking on condition of anonymity.Foreign Minister Farouq al-Shara, making no specific reference to the questioning request, said Damascus was keen to cooperate with the probe.He "affirmed that Syria is keen on cooperating fully with the international investigation committee and installing the appropriate mechanisms to do so", the official Syrian news agency SANA reported.

 Shawkat, who is married to Assad’s sister Bushra, was named in a report published last month, while Assad’s brother Maher’s name appeared in an unedited version.

Mehlis, the German prosecutor who won fresh powers from the Security Council to carry on with the probe, has complained that Syrian security figures interviewed in Damascus in September appeared to give only prepared responses.

The Lebanese source, who asked not to be named, said Mehlis had requested the men be questioned at the inquiry’s headquarters east of Beirut.

The Security Council voted unanimously last month for a resolution demanding Damascus cooperate fully with the inquiry into the Beirut bombing that killed Hariri and 22 others or face "further action".

Mehlis, who said that evidence pointed to Syrian and Lebanese involvement in the assassination, has also accused Damascus of failing to cooperate properly with his mission.

"BALL IN SYRIAN COURT"

Damascus has come under fierce international pressure since Hariri’s killing. It has already had to pull its troops out of neighbouring Lebanon after a 29-year presence.

The United States, France and Britain sponsored the Security Council resolution a week ago after Mehlis concluded in the preliminary report that Hariri’s assassination could not have been plotted without the knowledge of Syrian security officials and their Lebanese allies.

Assad, who has insisted that Damascus had no role in the killing, may eventually have to give up members of his own inner circle for trial or face possible economic sanctions.

The resolution, sponsored by the United States, France and Britain, obliges Damascus to detain any suspects named by Mehlis and make them available to U.N. investigators.

Speaking to reporters during a visit to Lebanon, U.S. Assistant Deputy Secretary of State for Near Eastern Affairs Elizabeth Dibble said the international community was waiting for answers from Damascus.

"The ball is now in the Syrian court to cooperate and we very much hope that the government of Syria will cooperate with Judge Mehlis in his investigation and that at the end of the day, there will be answers and that the perpetrators of the crime will be brought to justice."

Syria dismisses Mehlis’s report as politicised and has set up its own investigation into the murder.

The other five who Mehlis requested to interview were Major General Bahjat Suleiman, former head of the internal security branch at the general intelligence department; Lieutenant General Rustom Ghazali, ex-chief of the Syrian intelligence in Lebanon; Lieutenant General Thafer Youssef; Lieutenant General Abdul-Karim Abbas; and officer Jamea Jamea.

Jamea was an aide of Ghazali while both Youssef and Abbas were receiving training at a military academy in Beirut at the time of the assassination. Abbas is an officer at the military security body headed by Shawkat, while Youssef is "believed" to be a communications officer, the Lebanese source said.