The initial public offering will give the startup a valuation exceeding the 30 billion yen achieved at its last fundraising, the person familiar with the matter said, declining to be identified because the information is not public.

While Japan has moved to strengthen its corporate governance in recent years, Uhuru believes becoming the only Japanese firm on the AIM board will better help it attract capital and grow outside Japan, the person said.

Uhuru declined to comment.

"Britain's corporate governance is extremely strict but should make the company more able to respond to investors," the person told Reuters.

As part of its efforts to improve governance, Uhuru plans to install Andrew Rose, a veteran Japan hand who recently retired as a fund manager at asset manager Schroders, as an outside director late next month, the source said.

That will bring the number of external directors to seven, including three Britons, with Uhuru to halve the number of its executives on the board to three, the source said.

Last year, Uhuru received a 500 million yen ($5 million) investment from telco SoftBank Corp. Its other investors include Salesforce.Com, Mitsui & Co and Dentsu.

Uhuru opened its London office last year, putting it in close proximity to Cambridge-based SoftBank Group Corp subsidiary and business partner Arm.

Arden Partners and SMBC Nikko are advising Uhuru on the listing.

(Reporting by Sam Nussey; Editing by Himani Sarkar)

By Sam Nussey