"It has been decided to temporarily suspend forward sales and purchases. Authorised dealers (banks) are, therefore, advised not to buy from or sell to their customers foreign exchange on a forward basis with effect from today," the State Bank of Pakistan said in a circular.

It said forward commitments until October 14 would be honoured and banks might also cut forward deals in the inter-bank market to manage their Nostro accounts -- balances held abroad to finance trade transactions.

The circular follows a declaration of a state of emergency by the military leaders who overthrow prime minister Nawaz Sharif on Tuesday and a stream of circulars restricting foreign exchange ouflows on Thursday.

Bankers said the move is yet another attempt to pre-empt a drain on Pakistan's meagre foreign exchange resources.

They also said the move seemed aimed at limiting speculative forward trade by importers and exporters.

"Our volumes in the interbank market will be hit as there will be no forward trade with importers and exporters on spot deals," one banker said.