The chief investigator into the assassination of former Lebanese Prime Minister Rafik Hariri urged Syria on Tuesday to cooperate better with his team so it can "fill in the gaps" about the organizers and perpetrators of the terrorist act. German prosecutor Detlev Mehlis addressed the UN Security Council five days after issuing a report implicating top Syrian and Lebanese intelligence officials in Hariri's assassination and accusing Syria of cooperating in form but not substance with the investigation. Shortly before he spoke, US Ambassador John Bolton and French Ambassador Jean-Marc de La Sabliere said they expected to circulate a joint resolution very soon. It is likely to demand Syria's cooperation with Mehlis' investigating commission, though how strong the language will be - and whether the resolution will be under Chapter 7 of the UN Charter which can be enforced with military action - is still being discussed. Mehlis' investigation has been extended until Dec. 15 and he told the council his team will re-interview a number of witnesses, interview new ones, complete its examination of recently obtained evidence, and cooperate with Lebanese judicial and security authorities.