TOKYO - SoftBank Group Corp may be looking to raise around 2 trillion yen ($18 billion) in an initial public offering (IPO) of its mobile unit with the shares to be listed on the Tokyo Stock Exchange (TSE) by the end of this year, sources with knowledge of the matter said Monday.

According to a potential plan, SoftBank Group, owner of 99.99 percent of its subsidiary SoftBank Corp, will likely hold onto around 70 percent of shares after the IPO on the TSE's Fist Section, expected to happen by the end of the year.

The communications giant is also mulling the idea of having its telecommunications unit going public in London and other overseas markets, possibly at the same time.

SoftBank's billionaire Chief Executive Officer Masayoshi Son is reportedly seeking to raise funds from the stock offering for new investments and the reduction of debt.

SoftBank Group, based in Tokyo, has made a number of overseas acquisitions including US investment company Fortress Investment Group and British semiconductor designer ARM Holdings.

The Japanese telecom giant also holds stakes in US carrier Sprint, as well as stakes in some 1,000 companies including Yahoo! Japan and Alibaba.

The conglomerate said in a statement that various capital options are still being perused.

"We are always studying various capital strategy options. The listing of SoftBank Corp. shares is one such option, but no decision has been made to officially proceed with this course."

Following reports of the possible IPO on Monday, the company's shares advanced 288 yen, or 3.2 percent, to close at 9,223 yen.

Just prior to Donald Trump becoming president in the United States, Son met with the now-leader and said that his firm would invest $50 billion in startup companies in the US and help create around 50,000 new jobs there.

SoftBank was founded in 1981 and was the first carrier in Japan to offer Apple's iPhone.