Dec. 4 (Bloomberg) -- The perceived risk of owning the outstanding debt of Rinker Group Ltd., the Australian building- materials company bought by Cemex SAB in July, rose after Cemex halted talks on sales of assets totaling $4.25 billion.

Credit-default swaps on Rinker's bonds increased 22 basis points to 77.5 basis points, according to JPMorgan Chase & Co. This is the highest since Bloomberg began tracking the data in Sept. 2003. The contracts rise as perceptions of credit quality decline. A basis point, or 0.01 percentage point, is worth $1,000 on a swap that protects $10 million of debt.

Cemex, North America's largest cement maker, last week sold U.S. plants to Dublin-based CRH Plc for $250 million, calling off talks for a wider sale that would have been worth $4.5 billion. With less funds available to pay down debt, Cemex's credit rating may be cut which would in turn trigger a downgrade of Rinker's credit quality, said Anita Yadav, head of credit and hybrid research at UBS AG in Sydney.

``In today's environment and with the negotiations with CRH in doubt, people are questioning the chance of them being able to find another buyer and reduce the debt in the next 12 months,'' Yadav said.

``The rating agencies may say Cemex hasn't sold what they were expecting so they will downgrade the company a notch while it finds its feet,'' she said.

Both Rinker and Cemex, based in Monterrey, Mexico, have the second-lowest investment-grade rating of BBB from Standard & Poor's. Cemex purchased Rinker for $14.2 billion July 16, almost nine-months after it first bid for the Sydney-based company.

Credit-default swaps, originally conceived to protect creditors against default, pay the buyer face value in exchange for then underlying securities or the cash equivalent should the company fail to keep to its debt agreements.

To contact the reporter on this story: Laura Cochrane in Melbourne at lcochrane3@bloomberg.net.

Last Updated: December 4, 2007 02:52 EST