Pentagon - "concern" about U.S. military action in Libya

WASHINGTON (Reuters) - The Pentagon voiced concern on Thursday about the prospect of military action in Libya as pressure grows for U.N. backing of a no-fly zone or air strikes in Libya.

U.S. Defense Secretary Robert Gates, speaking to lawmakers in recent weeks, has cautioned a no-fly zone would be a risky operation requiring air strikes to cripple local air defenses.

"It would be logical if one of his concerns about a no-fly zone is the element of attacking Libyan air defenses, then an option of air strikes would be pretty similar," said Colonel David Lapan, a Pentagon spokesman.

"I think you could safely say there would be a concern about conducting military operations inside Libya."

Lapan said that five U.S. ships were now hovering in the Mediterranean. The aircraft carrier USS Enterprise, however, has been moved away from the Red Sea where it was positioned in recent weeks to the Arabian Sea, where it can support the ongoing war in Afghanistan.

Asked about possible preparations in the region for military actions other than a no-fly zone, should such a step be embraced by the White House, Lapan said: "From DOD perspective nothing has changed; all those discussions are still ongoing.

"When decisions are made we'll be ready to execute whatever we're asked to," he said.

(Reporting by Missy Ryan, Editing by Jackie Frank)