Raja Pervaiz Ashraf said the shortage comes with the onset of severe summer, the state-run Associated Press of Pakistan reported Wednesday.

Because of the shortage, electricity supply to homes is cut for several hours a day, further raising the people's misery index. Some estimates say the shortage may be as much as 4,000 megawatts, at a time when Pakistan is also gripped by soaring food prices.

Ashraf, a member of Pakistan's new ruling coalition that took over in March after months of violence and political instability, said the government is determined to resolve the issue.

Under an energy management plan to conserve power use, all commercial centers and markets are to be closed by 9 p.m.

Ajmal Baloch, president of a trade union, told APP that during the summer, shoppers prefer to come to markets at night and a 9 p.m. closing time would greatly inconvenience them.

He said people do not come to markets on official holidays, and the government's decision to close them on Fridays instead of on Sundays would further hurt business activities.

Despite attractive investment opportunities in a country of 160 million whose political climate is improving, rating agencies seem reluctant to raise their numbers on Pakistan because of the continuing insurgency, especially in tribal areas suspected to be Taliban and al-Qaida hideouts, residual political uncertainty and macroeconomic problems including shortages, growing fiscal deficits and soaring inflation.

Iranian Energy Minister Parviz Fattah is due to visit Pakistan later this month to discuss a proposal to supply 1,100 MW of electricity to the South Asian nation.

Iran's state-owned Islamic Republic News Agency has said during the recent visit of President Mahmoud Ahmadinejad to Pakistan, Iran renewed its offer to supply 1,100 MW of electricity to help meet Pakistan's energy needs, especially at the Gwadar port in Balochistan province and neighboring areas.

Iran currently provides 35 MW of electricity along the Pakistan-Iran border.

IRNA said Pakistan's conservation measures are designed to save 500 MW. It said Pakistani industrial units are being told to stagger their weekly holidays.