The company said it was working with its technical team that had been flown to the vessel to get it restarted.
The Catalunya Spirit has 29 crewmen on board and a full cargo and was headed for the Everett LNG terminal in Massachusetts when it lost propulsion.
Media in the US are giving the event much attention because of public perceptions stoked by the LNG industry's opponents about the safety of LNG marine transportation, despite its impeccable safety record.
The vessel is one of the industrys newest and has only been in service since March 2003.
The 138,000 cubic metres capacity carrier was on a regular delivery run from the Atlantic LNG production plant in Trinidad to Everett, the terminal owned by the US unit of Franco-Belgian company Suez. Everett LNG has been in operation since 1971.