UPDATE 2-Japan's Renesas set to receive $630 mln in loans-report

* Together with credit line, firm to secure 100 bln yen in capital-paper

* Three major shareholders to provide loan guarantees - Mainichi

* Renesas shares jump 21 pct after report

* Renesas declines to comment (Adds share price move, responses from firms)

TOKYO, June 14 (Reuters) - Japan's Renesas Electronics Corp is making final arrangements for a total of 50 billion yen ($630 million) in loans from four banks after its major shareholders balked at a request to inject fresh capital in the loss-making chipmaker, the Mainichi newspaper said.

Shares in Renesas, which is battling high costs and tough overseas competitors, jumped sharply on the report, gaining as much as 21 percent in morning trade to a one-month high.

The move would allow the world's fifth-largest chipmaker to secure a maximum of about 100 billion yen in capital, because it will also have a credit line of around 50 billion yen from banks, Mainichi said, citing a source close to the matter.

A Renesas spokesman declined to comment.

The company's major shareholders - Mitsubishi Electric Corp , Hitachi Ltd and NEC Corp - will provide loan guarantees to allow the company to secure the loan, the Mainichi said.

Hitachi and Mitsubishi Electric spokesmen said they had no comment on the Mainichi report, while NEC could not be reached immediately.

The four banks - Bank of Tokyo-Mitsubishi UFJ, Mizuho Corporate Bank, Sumitomo Mitsui Trust Bank and Mitsubishi UFJ Trust and Banking Corporation - were likely to provide the loans as long as the major shareholders guaranteed them, the Mainichi said.

Renesas, a product of successive mergers of the chip divisions of Mitsubishi Electric, Hitachi and NEC, had been planning to raise more than 100 billion yen in fresh capital and cut at least 12,000 jobs, sources have told Reuters.

The company wants to finalise its turnaround plan by July.

Renesas, which is the world's leading supplier of microcontroller chips used in cars, logged a large net loss this year after it was forced to shut eight of its factories because of natural disasters last year in Japan and Thailand. ($1 = 79.4150 Japanese yen) (Reporting by Yoko Kubota and Mari Saito; Editing by Richard Pullin)