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By Andrea Shalal

NELLIS AIR FORCE BASE, Nev., Feb 4 (Reuters) - U.S. Defense Secretary Ash Carter welcomed on Thursday a Saudi offer to participate in any ground operations in Syria launched by the U.S.-led coalition.

Carter said increased activity by other countries would make it easier for the United States to accelerate its fight against Islamic State militants.

"That kind of news is very welcome," he told reporters while on a visit to Nellis Air Force Base in Nevada.

Carter said he looked forward to discussing the offer of ground troops with the Saudi defense minister in Brussels next week. urn:newsml:reuters.com:*:nL8N15J5IL

He said the Saudi government had indicated a willingness to do more in the fight against Islamic State, which controls vast swaths of Syria and Iraq.

For instance, Saudi officials had said they would help marshal some Muslim countries to join in the fight, and to ensure that Iraqi and Syrian populations were able to prevent a reemergence of the military group later, Carter said.

Carter said he planned to use next week's meetings in Brussels to help encourage more broad-based support for accelerating the fight against Islamic State.

The Pentagon chief said the United States was also watching events in Libya very carefully but had made no decision on expanding its role there.

"The concern there is that Libya not get on a glide slope to the kind of situation that we find elsewhere, where (Islamic State), in a politically disrupted environment, seizes a foothold, gathers a piece of territory from which it is able to tyrannize people, and plot operations elsewhere," Carter said.

Islamic State forces have attacked Libya's oil infrastructure and established a foothold in the city of Sirte, exploiting a power vacuum in the country where two rival governments have been battling for supremacy.

Carter said the focus was now on political change in Libya, where the warring administrations are expected to form a unity government.

"The most important objective right now is to help Libyans come together and help put their government back together," he said.

Once that was accomplished, the U.S. government had said it was willing to join other countries, including Italy, in helping secure the country, he said.

(Reporting by Andrea Shalal; Editing by Eric Beech and Nick Macfie) ((eric.beech@thomsonreuters.com; 202-898-8319; Reuters Messaging: eric.beech.reuters.com@reuters.net))

Keywords: MIDEAST CRISIS/LIBYA USA