Venezuela's opposition on Sunday said it will investigate alleged wrongdoing within its ranks after a media outlet reported that a group of opposition lawmakers had unduly advocated for a businessman linked to the government of President Nicolas Maduro.

Opposition leader Juan Guaido said he would speak on Sunday about "acts of corruption," hours after website Armando.info reported that the alleged wrongdoing involved legislators from opposition parties First Justice and Popular Will.

The scandal comes as opposition efforts to oust Maduro lose steam and Guaido, who has been recognized by more than 50 countries as Venezuela's legitimate leader, struggles to launch a new wave of street protests.