Reserves held by SBP fell to $12.55 billion from $12.69 billion a week earlier, while those held by commercial banks rose to $4.25 billion, compared with $4.21 billion the previous week.

Foreign exchange reserves hit a record $18.31 billion in the week ending July 30 last year, but have since eased due to debt repayments.

Reserves were boosted in June last year by inflows of $411 million, including a $191.9 million loan from the World Bank, and a $196.8 million loan from the Asian Development Bank.

Higher export proceeds and a record inflow of remittances have also helped support Pakistan's foreign exchange reserves.

According to official data, remittances rose 19.6 percent to $6.33 billion in the first half of the fiscal year (July-June), compared with $5.29 billion in the same period a year earlier.

Islamabad has to start repaying an $8 billion International Monetary Fund loan in early 2012. Without additional sources of revenue, that will put further pressure on Pakistan's foreign exchange reserves.