(Reuters) - Congo's national election commission failed to account for $400 million of funds it received from the state, and awarded opaque procurement contracts ahead of the disputed December general election, an EU-funded civil society report said Monday.

       The report said the electoral commission, known as CENI, was also blighted by budget overruns, an issue that has plagued President Felix Tshisekedi's administration.

       It urged Congo's justice department to open investigations into the management of the funds allocated to CENI for the electoral process.

       Technical mishaps, missing materials and a last-minute extension of voting have stoked disputes over the December poll, leading main opposition candidates to allege fraud and call for a re-run.

       The report, based on studies by the Centre for Research on Public Finance and Local Development (CREFDL) with funding from the European Union, said the election commission received nearly $1.1 billion in public funding between 2021 and 2023.

       But only $711 million had been approved in the national budgets, leaving about $400 million unaccounted for.

       The electoral commission did not respond to a Reuters request for comment. A spokesman for the government of the Democratic Republic of Congo did not respond to a request for comment on the report.

       StarPicks

       MAXIS BUSINESS DRIVES THE SMART MOBILITY REVOLUTION

       "The chain of use of these funds has remained opaque, and this may have an impact on the results (of the election)," Valery Madianga, a public finance expert and one of the lead researchers of the report, told Reuters.

       "Public funds have been very badly used, or perhaps they have gone into obscure pockets," Madianga said.

       The report also said that 45 of the 54 public contracts the commission signed between 2021 and 2023 were awarded by mutual agreement, with only nine awarded through tenders.

       "This frequent recourse undermines the principle of transparency, fairness and economy of supply," the researchers said in the report.

       It added that around 14 million more ballots and electoral cards had been bought than necessary, and more than 80% of the warehouses the commission rented were privately owned, raising concerns about the security of sensitive electoral materials.

       The electoral commission has defended the poll's credibility, although it invalidated votes cast for 82 of the 101,000 legislative candidates over alleged fraud and other issues on Jan. 6.

       Congo's Constitutional Court on Jan. 9 confirmed Tshisekedi's re-election as president, following the disputed poll, while his ruling UDPS party is leading in the legislative race, according to provisional results announced early Sunday.

       (Reporting by Sonia Rolley; Writing by Portia Crowe; Editing by Bate Felix and Ros Russell)