The company says the shift away from London will consolidate and improve the trading of the company's shares and simplify its capital structure.

Thomson Reuters stock price in London has consistently trailed the price quoted in North America, providing an incentive for international investors to sell their more expensive New York shares and replace them with cheaper stock from London.

Thomson Reuters chief executive officer Tom Glocer says: "The equity markets are increasingly global and electronic, and our investors deserve the very best capital structure we can provide. Our Board has determined that consolidating the trading of our shares into a single, global and deep pool of liquidity, listed on the Toronto and New York Stock Exchanges, is in the best interests of all shareholders."

He says that since the merger between Thomson and Reuters, UK shareholders now only constitute five per cent of the combined shareholder base.

"Our commitment to customers, employees and other stakeholders in London, the United Kingdom and Europe is unchanged by where we list our shares. London is a vital global capital for the markets that we serve, and home to more than 5000 of our employees," says Glocer.

The proposed unification will have no impact on the firm's global businesses, operations, strategy, financial position or employees, he says.

The company will seek shareholder approval for the delisting in August.

The news will be a blow to the LSE, which has missed out on trans-Atlantic consolidation trends in the exchange marketplace and seen its market share eroded by new competitors. Ironically, news of the plan spurred a rally on the Footsie as traders piled in to the media group's shares.