Wendy's dissed McDonald's newly launched fresh beef burgers on Twitter. In this photo, people eat in a Wendy's outlet in New York City, April 24, 2008. Getty Images/ Spencer Platt

Hours after McDonald’s announced Tuesday that starting May, all its Quarter Pounders will be cooked with fresh beef, Wendy’s took to Twitter to mock the fact that all the other kinds of burgers made by its rival fast food chain still contain frozen beef.

"Hey @McDonalds, heard the news," Wendy's tweeted. "Happy #NationalFrozenFoodDay to you for all the frozen beef that's sticking around in your cheeseburgers."

This was not all. Wendy’s launched a barrage of tweets, each with a different photograph of a McDonald’s burger that was still going to be cooked with a frozen beef patty, as the latter’s standard hamburgers, cheeseburgers, and the Big Mac did not get upgraded to fresh beef.

And lastly, Wendy's reestablished its difference with McDonald's.

"Some people are going to use fresh beef in SOME cheeseburgers, SOME of the time. We believe in using fresh, never frozen beef in every cheeseburger everyday," the burger joint tweeted.

But why did Wendy’s restart burger wars with McDonald’s? "We wanted to make sure that people aren't confused about what is true and what is reality," Kurt Kane, Wendy's chief concept and marketing officer, told Business Insider on Tuesday.

"You shouldn't have to use a decoder ring to figure out what quality you're going to get" he added.

Kane also emphasized the fact that they have never been influenced by McDonald’s “in any way, shape, or form," but rather its rival was always influenced by its long-term commitment to fresh beef since it opened in 1969.

McDonald's USA President Chris Kempczinski said in a news release: “The switch to fresh beef quarter-pound burgers is the most significant change to our system and restaurant operations since All Day Breakfast [in 2015]. McDonald's is a burger company and there is no better place to start than with our burgers."

"Over the past two years, we have been listening to our customers and evolving our business to build a better McDonald's. We are proud to bring our customers a hotter and juicier quarter-pound burger at the speed and convenience they expect from us," he added.

In keeping with its last year’s commitment to switch out frozen beef in all its Quarter Pounders by mid-2018, the fast-food giant has already delivered its promised fresh beef at about 3,500 of its locations including cities like New York and Los Angeles.

By the beginning of May, the company looked to cover 14,000 locations across the United States. One of the crucial aspects to consider in its initiative to deliver fresh beef burgers was how the decision would affect the delivery services.

"If it slows down the drive-through, that's the critical part of our business," said Kempczinski. "And so we just had to spend a lot of time really making sure that as we were cooking only when someone ordered, we'd figured out a way to do it that wasn't going to slow down service time."