(Reuters) -Restaurant Brands International topped market estimates for quarterly sales and profit on Tuesday, driven by strong demand at its Burger King chain and steady traffic at Tim Hortons.

While Burger King had previously struggled to drive sales higher in the United States, the brand has doubled down on its efforts to draw more customers through improved marketing and new restaurant technology while also streamlining its menus and simplifying operations.

In the second quarter alone, the burger chain invested $12 million as part of its "Reclaim the Flame" turnaround plan, including $10 million towards advertising.

Sales trends, as a result, have improved, with profitability at the chain also bouncing back. Some analysts have noted the brand might even be ahead of plan in its turnaround.

Comparable sales at Burger King U.S. rose 8.3% in the reported quarter, fueling total comparable sales growth of 10.2% and beating analysts' average estimate of 4.5% increase.

Improving mobility in Canada has boosted sales at coffee chain Tim Hortons - with comparable sales in Canada jumping 12.5% - while its breakfast sandwiches and bagels have also pulled more customers.

Global comparable sales at the company rose about 10%, beating estimates of 5.75%.

McDonald's and KFC-owner Yum Brands have in recent weeks also topped expectations for quarterly sales and profit, propelled by increased traffic in stores due to new menu items and promotional offers.

Total revenue at Restaurant Brands rose to $1.78 billion in the second quarter from $1.64 billion a year earlier. Analysts on average had expected revenue of $1.75 billion, according to Refinitiv data.

On an adjusted basis, Restaurant Brands earned 85 cents per share in the quarter ended June 30, beating estimates of 77 cents.

(Reporting by Deborah Sophia in Bengaluru; Editing by Krishna Chandra Eluri)