Burger King wants to do something that McDonald's has never been able to accomplish

Burger King wants to start selling veggie burgers worldwide.

The fast-food chain introduced a special line of six meatless burgers last year in India, including a Veggie Whopper, a Spicy Bean Royale, and a vegetarian chili cheese melt.

The sandwiches have been so successful that the chain is now considering launching them in other vegetarian-friendly markets, according to Burger King India CEO Raj Varman.

"Looking at the response here, the global management is evaluating introducing some of these options going forward to other vegetarian-friendly markets like the UK," Varman told India news agency PTI, according to the Economic Times.

McDonald's, which also offers vegetarian options in India, has tried launching meatless burgers in the US on numerous occasions without success, CEO Don Thompson told investors in 2011.

"We ended up serving four a day," Thompson said.

Despite McDonald's failures, adding a meatless menu in markets like the UK and the US could be a smart move for Burger King.

Vegetarianism is on the rise and a growing number of people are defining themselves as "flexitarians," which means they eat a primarily plant-based diet supplemented by occasional meat consumption.

Sales of meat alternatives in the US rose to $553 million in 2012, up from $513 million two years earlier, according to market-research firm Mintel.

Meanwhile, Americans' per capita consumption of meat and poultry has declined more than 9%, from 221.6 pounds in 2007 to an estimated 200.8 pounds this year, according to the USDA.

And vegetarian menu options don't only attract customers who don't eat meat. They also increase the likelihood that meat-eating customers will come to your restaurant, according to Darren Tristano, executive vice president at Technomic.

"If options like a veggie burger exists, it reduces the veto vote and gives everyone in the party a chance to order what they want," Tristano told Businessweek.

Burger King currently offers a veggie burger in the US, but it's made with a MorningStar Farms Garden Veggie Patty - which anyone can buy in the freezer aisle of most grocery stores.

Burger King India's vegetarian menu offers many more sandwich options, as well as vegetable-based snacks, such as Vegetable Chili Cheezos (fried bites of cheese and vegetables with paprika) and Veggie Strips (fried strips with a vegetable filling of corn, green peas and carrots).

We reached out to Burger King for comment and will update when we hear back.