The government has raised the windfall tax on petrol and diesel exports with effect from August 3, according to an official order. The windfall tax on petrol exports has been increased to Rs 3.5 per litre from Rs 2.5 per litre, while the levy on diesel exports has been raised to Rs 24 per ltre from Rs 15.5 per litre.The latest revision is part of the Centre’s fortnightly review of windfall taxes on petroleum products. The government adjusts these levies based on changes in global oil prices, export margins and market conditions.Windfall taxes are imposed on petroleum products when refiners and producers benefit from unusually high gains due to elevated international energy prices.