Theresa May has told senior bosses of Japanese businesses that Brexit is "no small undertaking", but will allow the UK to forge a free trade deal with Japan.
The Prime Minister said she hoped the talks with major Japanese investors would be "very constructive" as she highlighted the improved UK growth forecast announced by the Bank of England earlier.
The heads of businesses including household names such as Mitsubishi, Honda, Nissan and Panasonic - which employ thousands of workers across the country - met at Number 10 amid concern over estimates of the impact of Brexit on economic growth.
Official estimates obtained by Sky News of the potential impact of non-tariff barriers - such as extra red tape, customs checks and rules of origin regulations - on various economic sectors, suggested the motor industry faces cost increases of between 5% and 13%.
And the economically important financial services sector stands to suffer a 5% to 10% cost increase.
Joined by Chancellor Phillip Hammond, Business Secretary Greg Clark and International Trade Secretary Liam Fox, Mrs May opened the meeting, saying: "As we look to the relationship between the UK and Japan we see already year-on-year trade between our two countries continues to increase, with Japans's investment in the UK reaching £46.5 billion in 2016."
She told them the Government's modern industrial strategy made the UK "more attractive".
And she added: "Just today we have seen the Bank of England raise its forecast for UK growth compared with its estimates three months ago.
"As we look ahead of course I recognise that UK's exit for the European Union is no small undertaking, but importantly it does present an opportunity to strike free trade deals around the world and build on our already strong relationship with Japan."
Around 879 Japanese companies employ 142,000 staff in the UK, according to figures from the Japan External Trade Organisation (Jetro) and the Japanese Embassy.
And the Asian nation has made significant investment in The City of London, with Japanese banks treating the UK capital as a financial gateway to the rest of Europe.
The BoE hiked its outlook for the UK economy, predicting growth of 1.8% in 2018, up from 1.6% previously.