Reuters reported on Sunday that the companies were close to announcing an agreement that would speed up their entry into the highly competitive and over-saturated market for mobile service in the United States.
As part of the agreement, Charter (chtr) and Comcast (cmcsa) will not be able to make "material" transactions in the wireless space for a year without the other's consent, Comcast said in a filing with regulators.
The material transactions may include acquisitions, investments or joint ventures that have a value of more than $200 million.
Comcast is moving into wireless as cable companies seek to offset customer attrition, as younger viewers shun high-priced subscriptions in favor of cheaper online options.
"(The partnership) will also enable us to provide more competition and drive costs down for consumers at a similar national scale as current wireless operators," Charter Chief Executive Tom Rutledge said in a statement.