U.S. regulators approved a merger Friday night between XM Satellite Radio and Sirius Satellite Radio.

Approval by the Federal Communications Commission was delayed because one commissioner, Deborah Tate, refused to vote for the merger until FCC Chairman Kevin Martin voted to fine the two companies for technical violations, The Washington Post reported. Both votes were tie-breakers.

The two companies first decided to merge 18 months ago. The deal creates a $13 billion satellite broadcasting giant, with subscribers having access to both XM and Sirius programming.

Critics, including consumer and broadcasting industry groups, say the merger gives one company a monopoly of the satellite radio industry. But the Justice Department found in March that it would not violate antitrust laws.

The FCC attached conditions, including requirements that consumers be permitted to select those channels they want and pay only for that package. While the selection is not yet available for car radios, it is expected to be soon.