President Donald Trump on Monday slammed AT&T as he arrived in the United Kingdom for a state visit, suggesting a boycott of the company over what he says is negative coverage by CNN.

AT&T BOYCOTT

After arriving in the U.K., Trump said he’d turned off AT&T T, +0.61% -owned CNN and that it gives the world a “false picture of USA.”

Trump has regularly complained about CNN’s reporting on his administration, frequently dubbing it “fake news.” In a pair of tweets, Trump said, “Why doesn’t owner @ATT do something?” and “I believe that if people [stopped] using or subscribing to @ATT, they would be forced to make big changes at @CNN, which is dying in the ratings anyway.” A spokesperson for AT&T didn’t return a request for comment. Shares of the telecom giant finished 1.7% higher on Monday.

It’s not the first time Trump has called for consumers to drop a well-known brand. In February 2016, for example, then-candidate Trump urged a boycott of Apple AAPL, +1.02% until the tech giant helped the Federal Bureau of Investigation break into the iPhone of one of the shooters involved in an attack in San Bernardino, Calif.

LONDON MAYOR FEUD

Before touching down north of London, Trump fired off two tweets about the city’s mayor, Sadiq Khan, who wrote in a newspaper column that the president is “one of the most egregious examples of a growing global threat” from the far right to liberal democracy.

Trump called Khan a “stone cold loser” and suggested the mayor focus on crime in his city instead of the U.S. president. “Kahn [sic] reminds me very much of our very dumb and incompetent Mayor of NYC, de Blasio, who has also done a terrible job - only half his height,” Trump said. Trump is staying in London for two nights.

See:Trump, London mayor trade barbs as president’s ceremonial Britain trip begins.

Trump is on a three-day state visit to the U.K. In addition to meeting Queen Elizabeth II, he will take part in D-Day commemoration ceremonies on both sides of the English Channel. After the U.K. visit he will make his first presidential trip to Ireland.

In a tweet he said the queen and the entire royal family “have been fantastic,” and added a “big Trade Deal is possible” with the U.K. “once it gets rid of the shackles.” That’s an apparent reference to Britain’s departure from the European Union.

Now read:Brexit Brief: Trump lands in the U.K., vouching for prominent Brexiteers.

MEXICO DEMAND

As Mexico was reportedly weighing its options to respond to the threat of U.S. tariffs on all of its exports, Trump tweeted that the U.S.’s southern neighbor should “as a sign of good faith” immediately halt migrants and drugs flowing to the U.S. border.

As The Wall Street Journal reported, a high-level Mexican delegation is in Washington this week for meetings with U.S. officials to discuss ways of reaching an agreement after Trump threatened a 5% tariff on all Mexican imports starting June 10 unless Mexico does more to stem the flow of Central American migrants crossing its territory to reach the U.S. The tariffs would rise each month to reach 25% by October, Trump has said.

Mexican Economy Minister Graciela Márquez said there are several roads that Mexico could take if the U.S. goes ahead with the tariffs, including resorting to multilateral organizations and hitting back with tariffs on selected U.S. goods.

See:Here are the 6 stocks under the biggest threat from Trump’s new tariffs on Mexico.

CHINA TARIFF DEFENSE

Also on Twitter, Trump defended his administration’s tariffs on Chinese goods, even as Beijing signaled a willingness to negotiate with Washington over trade issues.

“Many firms are leaving China for other countries, including the United States, in order to avoid paying the Tariffs. No visible increase in costs or inflation, but U.S. is taking Billions!” Trump wrote.

Also read:Why this country could emerge as a surprise winner from the U.S.-China trade battle.

On Sunday, Vice Commerce Secretary Wang Shouwen said China is “willing to adopt a cooperative approach to find a solution” to trade. Talks between the two sides broke down in May.

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