The U.S. already has nine such facilities, but the building of more LNG import terminals was proposed by companies when U.S. gas production began to decline in the early 2000s.

Occidental Petroleum Corp. (OXY), Sempra Energy (SRE) and Cheniere Energy (LNG) all put in proposals for new terminals, according to Dow Jones Newswires.

In recent years, however, an influx of U.S. gas supplies from vast, deeply buried onshore shale-rock has sharply reduced the demand for imports of foreign gas. U.S. gas prices have tumbled more than 60% from highs near $14 a million British thermal units seen in the summer of 2008, making the prospect of exporting LNG to the U.S. less compelling for overseas companies that can fetch higher prices for their shipments elsewhere.

The Federal Energy Regulatory Commission has approved the construction of more than two dozen new LNG terminals or expansions of existing terminals, but most of the projects are on hold, awaiting more favorable market conditions.

Occidental received FERC approval in 2005 for an LNG terminal near Corpus Christi, Texas. Almost five years later, the Los Angeles-based energy company has yet to begin construction of the terminal. FERC last year approved the company's request to delay the project's completion until April 2011.

Development of the terminal will depend on market conditions, including the availability of additional LNG supply. Cost estimates remain unclear.

Sempra's plans for an LNG terminal in Port Arthur, Texas, are similarly in limbo. The project, estimated to cost $800 million to $1.4 billion, received FERC approval in 2006. The San Diego-based company is still trying to secure contracts for the terminal's capacity before the company breaks ground.

Some companies continue to pursue new terminals, however.

New LNG export facilities in Qatar, Yemen, Russia and Indonesia have sent more gas cargoes into the global market, although the U.S. remains a "market of last resort"--the destination for LNG shipments when all other options have been exhausted. LNG flows to the U.S. averaged 1.3 billion cubic feet a day in the fourth quarter of 2009, up from 900 million cubic feet a day during the fourth quarter of 2008, according to Houston energy-investment bank Tudor Pickering Holt & Co.

Sempra's Cameron LNG terminal in Louisiana was dedicated in October and received a shipment from Qatar in November. The facility has an agreement with RasGas Co. Ltd., a joint venture between state-owned Qatar Petroleum and Exxon Mobil Corp. (XOM), for LNG deliveries through the end of the year.

Many LNG projects along the Gulf Coast are likely to be shelved because of supplies from shale formations in the region, but terminals proposed for the East and West coasts stand a better chance of completion if they can overcome local opposition. Downeast LNG aims to build a $400 million LNG terminal in Maine. The terminal is awaiting FERC approval.

Pipeline constraints in the Northeast and West have allowed only limited supplies of shale gas to reach those regions, providing some support for gas prices. But in the Gulf Coast, shale gas is competing with LNG cargoes, driving prices lower.