UPDATE 2-Ireland's CRH buys U.S. assets from Mexico's Cemex

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DUBLIN, Nov 30 (Reuters) - Irish building materials group CRH Plc (CRH.I: Quote, Profile, Research, Stock Buzz) will buy U.S. assets worth about $250 million from Mexico's Cemex (CMXCPO.MX: Quote, Profile, Research, Stock Buzz), which was required to sell them so its $15.3 billion buy of Rinker Group can go ahead.

CRH (CRH.L: Quote, Profile, Research, Stock Buzz), a leading supplier to the construction industry, and Cemex, the world's top building materials company by revenue, said CRH would buy Cemex's ready-mixed concrete and concrete block operations in Florida and its aggregates and ready-mixed concrete operations in Arizona.

Cemex (CX.N: Quote, Profile, Research, Stock Buzz), which has operations in more than 50 countries, said it would use the proceeds to reduce its debt.

The U.S. Department of Justice required Cemex to sell the businesses to avoid it becoming too dominant in the United States with its acquisition in July of Australia-based Rinker.

The Cemex business in Florida includes 26 concrete plants and 6 block plants, while in Arizona CRH will acquire two quarries and six concrete locations.

"Negotiations with Cemex regarding a wider transaction involving additional assets have been terminated," CRH said in a statement.

CRH, which already has operations in the United States, said the Cemex deal meant it had now spent 2 billion euros ($2.95 billion) so far this year on acquisitions in the United States, Switzerland, Turkey, China and the Netherlands.

Cemex's buy of Rinker was the largest-ever acquisition by a Mexican company. It beefed up Cemex's presence in the United States, which accounts for 80 percent of Rinker's revenues, while giving it a foothold in China and Australia. (Reporting by Paul Hoskins and Robert MacMillan in Dublin and Catherine Bremer in Mexico City; Editing by Gary Hill)