In a drive to clean up the impoverished country's polluted cities, the government has also ordered all public transport, especially some 150,000 diesel-run buses and lorries, to convert to compressed natural gas (CNG).

Officials said some 40,000 small vehicles had already been changed to CNG since 1996 under an environmental safety programme, replacing vehicles emitting harmful carbon.

"More use of CNG-fired transports would further help us to save money, as well as ensure clean air. That is why we are asking entrepreneurs to set up more CNG filling stations across the country," energy adviser Mahmudur Rahman said on Tuesday.

The Bangladesh government recently increased prices of diesel, petrol, octane and kerosene by about 17 percent on average in the wake of spiralling world oil prices.

Owners and operators of buses and lorries have called for a two-day countrywide transport strike from Wednesday in protest against increased fuel costs.

Transport fares have already gone up by about 20 percent since Sunday.

"Introducing a five-day work week will reduce use of transport by both public and private sectors, thus saving costly fuel and easing pressure on foreign exchange required to import oil," an energy ministry official said.

Bangladeshi workers used to working six days a week will have to stay on the job an hour longer, from 9 a.m. to 5 p.m., to make up for the extra day off.

Offices in Bangladesh customarily close at 4 p.m.

The news of two-day weekend delighted workers at all levels. But garment factory owners and exporters asked the government to change the weekend to Saturday and Sunday to provide better business opportunities.

"The whole business world remains closed on Saturdays and Sundays while they work on Fridays. If we close on Friday, it means we are shut for three days every week, business wise," said Annisul Huq, president of Bangladesh Garment Manufacturers and Exporters Association.