There is no timetable to launch the international board, said Geng Liang, president of the Shanghai Stock Exchange, on Wednesday.

"The drafting of rules for issuing, listing, trading and settlement have been finished, which was an important achievement," said Geng.

The listing of overseas companies on Chinese mainland exchanges involves complicated legal, accounting and foreign-exchange issues.

"The Shanghai Stock Exchange is still conducting research on these key issues on the framework that we have built," he said.