The Osaka Securities Exchange and Jasdaq Securities Exchange have begun talks on using each other's trading systems as a backup in case of a disruption caused by a terrorist attack or natural disaster, the two bourses said Tuesday.

The discussions follow a series of problems with the Tokyo Stock Exchange's trading system since late last year.

The OSE and Jasdaq said it is technically possible to use each other's systems if one of them should break down.

In late April, officials from stock exchanges and brokerages around the country met to discuss disaster response measures.

The start of talks between the OSE and Jasdaq may encourage other stock exchanges to work together more closely to keep trading systems functioning in the event of an emergency, industry officials said.

A Jasdaq official in Tokyo said other exchanges may also join the talks to set up a computer system to handle transactions if trading is halted on one of the exchanges.

Meanwhile, Jasdaq and the OSE dismissed a report Tuesday morning by the Asahi Shimbun that the OSE may propose a merger with Jasdaq.

The paper, citing an anonymous source, said on its Web site that a holding company may be established to control both exchanges.

Shares of the Osaka Securities Exchange slid 5.19 percent to 1.47 million yen in Osaka after a suspension on trading in the shares following the report was lifted at 9:36 a.m.