There were multiple planning calls between campaign officials and Republican Party state operatives with Giuliani being involved in at least one call, one source said, in efforts to stop Joe Biden's victory when Congress met on Jan 6, 2021.
Trump and officials are facing several probes after failing to accept the election result, which is decided by the electoral college, where each person's ballot goes toward a statewide tally, requiring the votes of at least 270 electors for victory.
The former president's campaign lined up supporters to fill elector slots, had rooms for fake electors to meet and circulated draft certificates, CNN reported.
Bob Costello, a lawyer for Giuliani, and Liz Harrington, a spokesperson for Trump, did not immediately respond to requests for comment.
(Reporting by Costas Pitas; additional reporting by Karen Freifeld; Editing by Bill Berkrot)