Brazil's vehicle imports grew to 199,366 units in 2011, up 87.4 percent from the year of 2010, the country's Auto Importers Association (Abeiva) said Wednesday.

The auto imports by its member companies were up 5.82 percent last year, Abeiva said, adding that the growth should be attributed to the increasing number of new car models.

The association's President Jose Luiz Gandini estimated that the sales of imported cars would fall by 20 percent this year as the government in September raised the industrial product tax (IPI) on motor vehicles to between 37 and 55 percent, up from a range between 7 and 25 percent.

The measure came after Brazilian domestic automakers had been hit hard by the flooding of cheap imported vehicles due to the country's strong currency real.

Therefore, vehicles with less than 65 percent domestic content manufactured outside Mexico and members of the South American Mercosur would face a price hike due to the new tax structure.

Mercosur, consisting of Argentina, Brazil, Paraguay and Uruguay, was established in 1991 in a bid to promote the region's free trade and liquidity of goods, people and currency.

The measure came into force on Dec. 15 last year, but it didn't significantly affect the sales of imported cars in the world's fourth-largest auto market, as the Brazilians in December would spend their "13th month salary," or Christmas bonus set by the country's law.

Gandini said the implementation of the tax increase was unconstitutional, but he could not confirm whether Abeiva would file a lawsuit to block the government's plan.