PARIS, Jan 17 (Reuters) - French gas grid operator GRTgaz said a force majeure situation in Algeria and tensions in the global gas market were impacting deliveries of liquefied natural gas (LNG) to southern France.

Deliveries to the Fos-sur-Mer terminal were at about 40 gigawatt-hour (GWh) per day, compared with almost double that at 70 GWh per day needed for this period of the year when there is increased demand for power and heating, GRTgaz chief executive Thierry Trouve told journalists on Tuesday.

Trouve said there was enormous demand for gas for power generation in southern France, due to the cold weather, at about 85 GWh per day.

He added that tensions in the world gas market, with expected U.S. gas production going to Asia instead of Europe, were also exacerbating the problem.

"We are doing everything to have more LNG deliveries by end February," Trouve said.

(Reporting by Bate Felix; Editing by Sudip Kar-Gupta) ((bate.felix@thomsonreuters.com; +33 1 49 49 55 70; Reuters Messaging: Reuters Messaging: bate.felix.reuters.com@reuters.net; Twitter: @BateFelix))