The backing of the US Federal Communications Commission's chair for a merger of wireless companies does not seem to be enough to push it over the line, with 10 state attorneys-general filing a case opposing the merger between the American companies T-Mobile and Sprint.

The merger between T-Mobile and Sprint, the third and fourth biggest wireless carriers in the US, has moved a step closer with the chairman of the Federal Communications Commission, Ajit Pai, officially giving his support to the deal.

Two US politicians have written to the chairman of the Federal Communications Commission, Ajit Pai, asking him to prevent wireless companies from operating in the 24 GHz band, which will be used for 5G networks, until weather forecasting operations are protected.