Hailing the "broad and deep" relationship between China and the United Kingdom, British Prime Minister Boris Johnson has said he wants to be "ambitious with greater trade and investment between the countries" in a congratulatory message issued on Monday.

The statement was released to coincide with a reception held by London's Chinese embassy, commemorating the 70th anniversary of the founding of the People's Republic of China.

Richard Moore, director general for political affairs at the British Foreign and Commonwealth Office, read the message from Johnson to the assembled guests.

"I would like to share my congratulations on the 70th anniversary of the founding of the People's Republic of China, in the year that we also celebrate 65 years of UK-China relations at chargé d'affaires level. I would like to send my best wishes to you, your colleagues and the many Chinese nationals residing in the UK," said the statement from the prime minister.

"The UK's relationship with China is broad and deep, delivering great benefits for both our countries," it went on to say, "and this relationship will continue to be important as the UK prepares to leave the EU.

"I want to be ambitious with greater trade and investment between our countries, and stronger people-to-people links. As global powers, the UK and China must work together to lead the international response on addressing global challenges, such as climate change, and protecting free trade," it concluded.