DETROIT - Billionaire investor Kirk Kerkorian's Tracinda Corp. has made a US$4.5-billion cash offer for DaimlerChrysler AG's troubled U.S.-based Chrysler unit.

Tracinda said Thursday it wants "to build and strengthen'' the troubled automaker and "will offer the UAW and Chrysler management the opportunity to participate as equity partners in the transaction.''

Other potential bidders for Chrysler include Canadian auto parts company Magna International Inc.

Han Tjan, head of corporate communications for DaimlerChrysler in New York, said the German-American automaker is talking with possible partners about a sale and that the chairman is satisfied with the process.

"All of our options are still open. For us to talk about (Tracinda) is speculation,'' Tjan said.

California-based Tracinda said its offer is subject to Chrysler reaching a new collective bargaining agreement with the United Auto Workers, as well as a deal with DaimlerChrysler on sharing the unfunded pension liabilities and health care costs of Chrysler retirees.

DaimlerChrysler shares climbed $2.39, or three per cent, to $83.38 on the New York Stock Exchange after the announcement.

Kerkorian long has had interest in automotive companies.

Late last year he dumped the last block of what once was a nearly 10 per cent share of General Motors Corp., the world's largest automaker. He previously was a major shareholder in Chrysler Corp.