Tim Hortons and Burger King say they will become Restaurant Brands International when their tie up closes, which is expected to happen this week.

In August, Burger King agreed to pay $US11 billion ($A11.90 billion) to buy Tim Hortons, a Canadian chain known for its coffee and doughnuts. Tim Hortons shareholders approved the combination on Tuesday.

US regulators have cleared the deal and the companies expect Canadian regulators to sign off on Friday, making the sale official.

Restaurant Brands International will be based in Canada, and its 18,000 locations in 100 countries will make it the world’s third largest quick service restaurant company.

The companies said shares of Restaurant Brands will trade under the ticker symbol “QSR” on the New York Stock Exchange and the Toronto Stock Exchange.

3G Capital, which controls Burger King, will have a 51 per cent stake in the combined company.

Shares of Burger King Worldwide Inc lost $US1.34, or four per cent, to $US32.48. Tim Hortons stock fell 78 cents to $US82.98.

AP