Diesel will return to historical levels. After several forecasts pointing to an increase of four cents, taking into account Thursday’s closing prices, diesel is expected to rise by six cents a liter and gasoline by four cents next Monday.

According to the latest forecasts, diesel will rise by six cents a liter, and gasoline will fall by four cents a liter.

ISP: Reduction of 22.2 cents per liter for diesel and 26.3 cents for petrol
According to the government, the ISP cut next week will be 22.2 cents per liter for diesel and 26.3 cents for petrol, which translates to an extra 1.2 cents for petrol and an extra 0.4 cents for diesel.
According to a statement issued by the Ministry of Finance today, “Taking into account the perspective of price developments next week and the price changes observed in the past two weeks, there will be a further reduction in the prices of Internet services. [Imposto Sobre os Produtos Petrolíferos] in both fuels, as of next Monday, June 20.”
Thus, he noted, "the tax burden (ISP + VAT) was reduced by an additional 1.2 cents per liter of gasoline and 0.4 cents per liter of diesel."

In the same statement, the Department of Finance stated that “over the course of the next week, the global tax burden on fuel has been reduced through the two measures in place - the weekly ISP audit mechanism and the reduction of unit rates of this tax to its equivalent.  At a VAT rate of 13% – for a total of 22.2 cents per liter for diesel and 26.3 cents per liter for gasoline,” with “in addition to these amounts the carbon tax not being updated by about six cents per liter.”
According to the government, “the ISP rate for diesel is reduced to the minimum allowed under Directive 2003/96/EC, issued on October 27,” adding that “Portugal had already asked the European Commission, in April, not to be bound by the application of the lower limits that imposed by the aforementioned directive, under Article 19 of it, and the evaluation of the request by the services of the European Commission is in progress.”
The trusteeship also reported that “within the scope of the weekly review of the Internet Service Provider Modernization Mechanism, which guarantees the return of any extraordinary value-added tax revenue in light of the price development perspective, the situation will be reassessed next Friday, June 24.”
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