British Prime Minister Theresa May called her trip to China "fascinating and productive" as she addressed a group of business leaders in Shanghai on Friday before wrapping up her three-day journey.

"This week, they have been finalizing deals in sectors as diverse as financial services, education, energy and healthcare," she said of the leaders of over 50 British business and commercial organizations that accompanied her on her trip. "The UK and China are opening a new chapter in our 'golden era'."

She spoke at the China-UK Business Forum in China's financial hub.

Earlier on Friday, May and her husband, Philip May, toured Yuyuan Garden, a famous classical garden in Shanghai, and made papercuttings by themselves.

The United Kingdom's prime minister started her visit in Wuhan on Wednesday. In Beijing, she met with President Xi Jinping and held the China-Britain annual meeting between heads of government with Premier Li Keqiang.

"As I've traveled around China over the last few days, I've seen that we have the potential to do so much more together," she said at the forum, adding that she has been "struck by the level of enthusiasm for British brands, British culture, British goods and British services".

"China and the UK both have proud histories of innovation stretching hundreds, even thousands of years. That spirit of invention is still very much alive today, and if we pool our talents further, the results could be extraordinary," she said.

"The fast-changing world we are in brings many opportunities for businesses in both our countries."

May said UK business leaders who accompanied her are "completely committed to forging lasting relationships with businesses, investors and customers in your country".

Trade volume between China and the UK is continuing to grow, she said.

"Chinese investment is helping the UK develop infrastructure and create jobs. Nearly 50,000 British businesses import goods from China, while more than 10,000 sell their goods to customers here," she said.

The visit has brought the signing of a dozen deals worth about 9 billion pounds (80.7 billion yuan, $12.75 billion) in areas including Belt and Road construction, finance, innovation, agriculture and technology, the Ministry of Commerce announced on Thursday.