Comcast Chairman Brian Roberts and NBC Universal President Jeff Zucker are expected to appear at the hearing held by the Senate's antitrust subcommittee, which will probably take place in late January, said Dawn Schueller, a spokeswoman for Sen. Herb Kohl.
It will consider implications of the merger for consumers and the cost that they'll pay for cable, said Schueller.
Other witnesses will likely include a representative of a consumer group and a spokesman for a rival company, she said. Neither has been identified.
Antitrust experts have said that Comcast Corp's NBC Universal deal faces a long and intense regulatory review that will likely end in approval only after the cable giant agrees to give rivals access to NBCU's television shows and movies.
(Reporting by Diane Bartz; Editing by Richard Chang)