UK-listed firms will become the first foreign companies to be able to list in mainland China under a new stock link, the Treasury said.
Chancellor Philip Hammond is due to launch the London-Shanghai Stock Connect on Monday.
Firms will sell shares through dual listings on the Shanghai and London Stock Exchanges.
The UK government said the project will open up British firms to new investors.
The initiative will also allow companies from each country to raise capital in the other.
“Stock Connect is a groundbreaking initiative, which will deepen our global connectivity as we look outwards to new opportunities in Asia,” Mr Hammond is expected to say at the launch, according to a statement from the Treasury.
“London is a global financial centre like no other, and today’s