BRASILIA, May 21 (Xinhua) -- Brazilian truck drivers on Monday blocked key highways and disrupted cargo shipments to protest a rise in diesel prices and demand a reduction in fuel taxes.

Protesters blocked access to highways across at least seven states, including Sao Paulo, Minas Gerais, Rio de Janeiro.

Truck drivers had threatened last week to take action unless the federal government met their demands.

Fuel costs account for 42 percent of their working expenses, the drivers said, so lowering taxes would help counter the rise in gasoline and diesel prices, which have shot up nearly 16 percent in the past 12 months.

The price hike is a result of new pricing policies implemented by the state-run oil giant Petrobras, which now passes on to consumers any variations in the price of oil on the international market.

The truck drivers have the support of the owners of gasoline stations, who have also seen their profit margins shrink.

Brazil's President Michel Temer was to meet with aides later in the day to discuss the rise in fuel costs and possible tax breaks, the Agencia Brasil news agency reported.