A logo of Toshiba Corp is seen on a printed circuit board in this photo illustration taken in Tokyo July 31, 2012. REUTERS/Yuriko Nakao

TOKYO (Reuters) - A Japanese government-backed fund and policy bank are considering a joint bid with Broadcom Ltd AVGO.O for Toshiba Corp's 6502.T semiconductor business, a move that would vault the U.S. chipmaker into the lead to buy the prized unit, the Asahi newspaper said on Wednesday.

A bid by Innovation Network Corp of Japan and the Development Bank of Japan with Broadcom would appear to be aimed at preventing Toshiba’s chip technology from going to rivals in China or South Korea, the Asahi said, citing an unidentified source.

INCJ Chairman Toshiyuki Shiga said on Tuesday the fund was looking at the chip auction although it had not participated in the first round of bidding.

People familiar with the matter have told Reuters INCJ might invest in the business as a minority partner - a move that would help the government prevent a sale to bidders it deems risky to national security.

INCJ did not immediately respond to a request for comment outside business hours.

Media representatives for California-based Broadcom could not immediately be reached for comment on the Asahi report. A DBJ spokesman declined to comment. A DBJ spokesman declined to comment on the report.

Toshiba is selling the memory business, which it this month spun off as a separate unit, to help cover billions of dollar in writedowns from its U.S. nuclear unit Westinghouse Electric Co, which filed for U.S. bankruptcy protection from creditors last month.

Broadcom, which has partnered with private equity firm Silver Lake Partners LP [SILAK.UL], put in the highest first-round offer of 2.5 trillion yen ($23 billion) for the chip business, while Taiwan's Hon Hai Precision Industry Co 2317.TW, the world's largest electronics contract manufacturer, offered 2 trillion yen, a person familiar with the matter has said.

The other bidders are South Korea's SK Hynix Inc 000660.KS and U.S. chipmaker Western Digital Corp WDC.O, which has a joint venture in Japan with Toshiba's chip unit.