The Hong Kong-based Economic Times and the Hong Kong Standard said companies had been ordered by the central bank to bring home their foreign exchange by Thursday.

Asked to comment, a central bank spokesman said only that the State Administration of Foreign Exchange (SAFE) was in charge of foreign currency matters.

Wu would discuss "issues concerned with the administration of foreign exchange," according to a statement by the state council information office.

An official with the ministry of foreign trade and economic cooperation said he had not seen any central bank document calling for the return of foreign exchange.

"China has rules that it is illegal for trading companies to retain foreign exchange earnings overseas and China is now cracking down onirregularities," said the official, who is responsible for trade financing.

An executive in the Bank of China's foreign exchange department said export earnings of most Chinese trading firms held overseas were deposited with Chinese bank branches.

Chinese authorities have announced a crackdown on foreign exchange irregularities aimed at stemming capital outflow that reflects a lack of confidence in the yuan.

A nationwide check on foreign exchange transactions and overseas debt would be conducted, according to a state council circular made public on Sunday.

The circular warned of punishment for banks who illegally sold foreign exchange and trading companies who falsely obtained foreign exchange. It ordered tighter controls on short-term foreign debt issues.

The Hong Kong Standard, quoting an official with the state development planning commission, said the order to bring home foreign exchange was issued at the start of this month.

The official was quoted as saying that rumours spread by speculatorsabout a devaluation of the yuan had prompted firms to retain their foreign exchange in offshore accounts.

This had sparked buying of foreign exchange in China, resulting in a black market rate of nine yuan to the dollar, far higher than the official rate of 8.28.

China has repeatedly promised not to devalue the yuan, and most economists believe a cheaper yuan would do more harm than good to the Chinese economy by driving up the price of imports and discouraging foreign investment.

China's currency is convertible mainly for trade purposes on the current account, although buyers of foreign exchange must provide evidence of an actual trade-related need.

The capital account is largely closed.

Reliable estimates of capital flight are impossible to obtain, but an "errors and omissions" category in the balance of payments report gives a clue. Last year it was $16.9 billion, and this year it is expected to be much higher.

China's foreign exchange reserves have remained stable at around $140 billion thisyear, despite a $31 billion trade surplus in the first eight months and $27 billion of direct foreign investment over the same period.