BRASILIA, April 7 (Reuters) - Executives from Brazil's second-largest engineering company, Andrade Gutierrez, have testified that President Dilma Rousseff's 2014 reelection campaign was partly funded with kickbacks from large infrastructure projects, a newspaper reported on Thursday.
The testimony, part of a plea bargain deal with 11 executives, would be the strongest link yet between the widening "Operation Car Wash" probe and Rousseff's campaign, the Folha de S.Paulo paper said.
The allegations may bolster the case of the main opposition party PSDB, which has demanded that electoral authorities annul Rousseff's 2014 reelection for using illegal funding.
Plea bargain deals are strictly confidential until the testimonies are collected by prosecutors and accepted by a judge. A source last month confirmed that Andrade Gutierrez executives had signed a plea deal, which was being handled by federal prosecutors as it involved politicians.
Representatives with Andrade Gutierrez and Rousseff's Workers' Party did not immediately respond to requests for comments. Rousseff has previously denied any wrongdoing.
The executives said bribes were paid to win contracts in projects, including the Angra 3 nuclear power station, the Belo Monte hydroelectric dam and three stadiums built for the soccer World Cup held in Brazil in 2014, Folha reported.
The paper had previously reported that Andrade Gutierrez executives admitted the scheme was also used in Rousseff's 2010 election campaign. (Reporting by Silvio Cascione; Editing by Bernadette Baum)