TOKYO, March 4 (Reuters) - Shares in Japanese chip materials maker JSR Corp jumped 4.6% to 4,238 yen in early Tokyo trading on Monday following a media report that state-backed fund Japan Investment Corp (JIC) plans to launch a tender offer for the shares this month.

JSR, a major maker of photoresists used in chipmaking, announced last June it would be acquired by JIC, which is overseen by Japan's industry ministry, in a $6.4 billion deal aimed at driving consolidation within the sector.

The tender offer was slated to begin at the end of last year but JIC in December announced a delay to late February at the earliest, citing a delay in a Chinese antitrust review as the reason, saying it would update if the offer has not begun by March-end.

Negotiations with Chinese authorities are now on track with JIC planning to launch the tender offer this month, the Nikkan Kogyo newspaper reported without citing sources.

JSR shares have been trading at a discount to the tender offer price of 4,350 yen per share, reflecting investor doubts about whether the deal will achieve regulatory approval.

JIC's CEO Keisuke Yokoo said in December there were no issues with the China regulator. "We expect it to be done by March-end of the current financial year," he said.

(Reporting by Sam Nussey; Editing by Kim Coghill)