UPDATE 2-Cemex eyes Australia asset sales to reduce debt

(Adds background about debt and U.S. market)

MEXICO CITY, Aug 6 (Reuters) - Mexico's Cemex, the world's No. 3 cement maker, said on Wednesday it may sell assets in Australia to reduce its debt load.

Cemex (CMXCPO.MX) said it could sell 16 plants that make pipes and other concrete products and operate under the Humes brand.

Operating in more than 50 countries, Cemex faces a battered U.S. housing market and a slowdown in key European markets such as Spain, where cement volumes slumped 26 percent in the second quarter.

The company, with net debt of about $18 billion, said it has hired Merrill Lynch to advise it in the process of selling the Australian operations. Humes had sales of $234 million last year.

Cemex has said it expects volumes in the U.S. industrial, commercial, residential and public sectors to fall this year as foreclosures increase.

Monterrey-based Cemex generates about a quarter of its earnings before interest, taxes, depreciation and amortization, or EBITDA, in the United States.

The company boosted its U.S. market share last year with a $16 billion takeover of Australian building materials company Rinker, which had 80 percent of its operations in the United States. (Reporting by Noel Randewich; editing by Carol Bishopric)