If the current trend continues, diesel will be deregulated in three months.
An official statement said the difference between the cost of diesel production and the retail selling price has narrowed to Rs 1.33 per litre from Rs 2.49 last month.
This was made possible because of softening international oil rates and the new government continuing with monthly price increases.
Diesel prices were on Thursday hiked by 50 paise per litre.
Rates have cumulatively risen by Rs 11.24 per litre in 18 instalments since January 2013 when the previous United Progressive Alliance government had decided on small monthly hikes.
The government had in January 2013 decided to raise diesel prices in small doses of 40-50 paise per litre every month till the losses, which are made good through government subsidy, are completely eliminated.
Officials said the monthly increases had trimmed losses to less than Rs 3 per litre in May last year before a fall in rupee value led to losses on diesel sale widening to Rs 14.50 per litre in September 2013.
Since then, monthly increases have continued and the rupee has strengthened.
The losses
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