TOKYO: Japan's biggest mobile carrier NTT Docomo will be taken over by its government-backed parent company in a $40-billion tender offer, the firms said Tuesday, as telecoms competition hots up with 5G on the horizon.

The move comes with Docomo and other Japanese telecoms firms under government pressure to cut the price of mobile phone services, and is expected to help the company boost investment in next-gen technology.

"Today we decided to make Docomo a wholly owned company," Chief Executive Jun Sawada of Nippon Telegraph & Telephone (NTT) told reporters, promising the move would enhance the carrier's "competitiveness and growth".

NTT, which currently holds 66 percent of NTT Docomo's shares, is proposing a price of 3,900 yen ($37) per remaining share to buy out the whole subsidiary, it said.