The lobbying push came ahead of Wednesday's hearing to examine the deal before the Senate Judiciary Committee's subcommittee on Antitrust, Competition Policy and Consumer Rights.
In December, Verizon agreed to buy wireless airwave licenses, known as spectrum, from cable companies including Comcast and Time Warner. Under a separate deal announced simultaneously, Verizon and the cable companies agreed to cross-sell each other’s services.
The side deal would allow consumers to buy the cable companies’ services in Verizon Wireless stores and allow the cable companies to sell Verizon contracts as part of their packages.
“Instead of planning for a stable future that provides a world-class telecommunications infrastructure for America, Verizon has chosen to strive for the lowest common denominator in the industry, pursuing a low-wage, poor-service and limited choice alternative that benefits only their top executives at the expense of everyone else," IBEW President Edwin Hill said.
Communications Workers of America President Larry Cohen said the deals would discourage future investment in broadband Internet networks.
"This deal will freeze then diminish wireline buildout. In short, we need policy that brings 100 percent of our nation into the 21st Century information-based global economy," Cohen said.
Supporters of the deal note that the cable companies had no immediate plans to use their stockpile of spectrum, and Verizon will be able to use the spectrum to power its next-generation wireless network.
Verizon has also insisted that the cross-marketing deals are unrelated to the spectrum sale.
A Verizon spokesman declined to comment on the union's lobbying push.
The Federal Communications Commission and the Justice Department are reviewing both deals.