Prime Minister Manmohan Singh appeared to rule out cutting prices of petrol and diesel till oil companies stop making losses on fuel sales.

Contending that there were "limits to which the government can go on subsidising", Singh said it will wait till oil companies stop making losses before considering cutting petrol and diesel prices.

"When we see that the Indian oil [Get Quote] companies are able to sustain a reduction, that will be the right (time for such a) decision," Singh told reporters late last night on way back to

New Delhi from his three-day maiden visit to energy rich Gulf countries.

Oil companies have started making profit on sale of petrol but they continue to incur losses on diesel sales.

"Oil companies have to bear a very heavy burden," he said.

Indian Oil, Bharat Petroleum and Hindustan Petroleum currently make a profit of Rs 4.12 a litre on petrol but lose Rs 0.96 per litre on diesel.