SoftBank, the majority owner of the U.S. wireless network Sprint, is reportedly in the 'final stages' of talks over the purchase of rival network T-Mobile, reports in Japan claimed on Christmas Eve.

The Japanese parent company SoftBank wants to use Sprint shares to buy T-Mobile from German firm Deutsche Telekom, in a deal thought to be worth around $19 billion, Reuters reports.

The deal could be finalised as soon as next spring, according to Japanese news site Nikkei's sources.

Any agreement would give a combined Sprint / T-Mobile network a better shot at competing with the dominant AT&T and Verizon networks in the U.S., as the big four would become a big three.

Winning approval

AT&T itself agreed to buy T-Mobile for $39 billion back in 2011, but the buyout ran afoul of government competition regulators and, amid the hassle, AT&T ended up walking away from the deal.

Any Sprint and T-Mobile merger would also be subject to similar scrutiny, but given the respective market shares of the two networks, it may have more chance of winning approval from the FCC.

Word of a potential takeover emerged last week, with reports claiming both sides were seeking out regulatory concerns.