AT&T has agreed to buy T-Mobile USA from Deutsche Telekom for $US39 billion, in a deal that will create the largest carrier in the US and promises to reshape the industry.
The transaction - one of the largest since the onset of the financial crisis - is expected to incite a fierce battle in Washington as regulators scrutinise the impact of the agreement on competition and consumers.
The deal will leave just three big mobile phone companies in the US: AT&T, Verizon and the much smaller Sprint Nextel.
Critics say it could lead to higher prices - T-Mobile was offering some of the lowest rates in the country, keeping pressure on its competitors, Sydney Morning Herald reports.
Deutsche Telekom AG's decision to sell T-Mobile to AT&T had the German company's stocks soaring Monday, but the deal will still have to pass muster with the Federal Communications Commission, which regulates competition in communication industries.
AT&T's acquisition, which was announced Sunday, will create a new corporate entity with 43 per cent of the U.S. market share, sparking antitrust accusations and fears over higher customer bills.
Deustche Telekom had been looking to unload T-Mobile for years because, although it has been profitable, it lacked the scale to compete with AT&T, The Mark reports.