MONTERREY, Mexico, Nov 11 (Reuters) - Mexico's Cemex, the world's No. 3 cement maker, offered on Wednesday to replace commercial paper with up to 12.5 billion pesos ($951 million) in convertible securities as part of its debt refinancing.

Cemex (CX.N: Quote, Profile, Research) (CMXCPO.MX: Quote, Profile, Research) convinced its creditors to refinance $15 billion in bank and bondholder debt until 2014, but has agreed to sell assets and raise capital via equity and bond issues.

"The amount of the offer is for a minimum of 3 billion pesos and a maximum of 12.5 billion pesos," the company said in a statement to the Mexican stock exchange. The company said the offer would be from Nov. 11 through Dec. 9.

Under the terms of the deal, Cemex will issue 10-year securities that can be converted into a maximum of 400 million shares on the Mexican bourse.

Cemex became the top cement company in the United States in 2007 after purchasing Australia's Rinker for $16 billion, but the deal saddled Cemex with a huge amount of debt just as the U.S. housing crisis broke, sending its sales sharply lower. ($1=13.1475 pesos) (Reporting by Gabriela Lopez; Editing by Lincoln Feast)