Brasilia, April 17 (IANS): Five opposition parties have accused Brazilian President Dilma Rousseff of vote-buying ahead of Sunday's impeachment ballot in the lower house of Congress.

The Brazilian Social Democracy Party, the Democrats, the Socialist People's Party, the Brazilian Labour Party and the Social Christian Party filed the complaint with the federal police on Saturday, EFE news reported.

In the complaint, the opposition parties question the legality of a decree signed on Friday that makes the northern state of Amapa the title-holder of most of the land in that Amazonian region.

The decree is aimed at convincing lower house lawmakers from that state to vote against impeaching Rousseff, the opposition parties said.

Rousseff is accused of using loans from state-owned banks and other fiscal maneuvers in 2014 and 2015 to disguise the size of the budget deficit.

A two-thirds majority is required in the lower house to send the impeachment matter to the Senate, where a simple majority will be enough to compel Rousseff to step down for 180 days pending completion of a trial.

Vice President Michel Temer, whose PMDB party -- the largest in Brazil's ruling coalition -- announced last month that it was formally breaking off with Rousseff's centre-left Workers Party administration, would then become acting president.

Temer himself is under investigation for alleged involvement in an illegal ethanol-purchasing scheme.