WASHINGTON — President-elect Donald Trump launched a Twitter attack on China Sunday, warning Beijing against devaluing its currency and taxing US products in order to “build a massive military complex.”

“Did China ask us if it was OK to devalue their currency (making it hard for our companies to compete), heavily tax our products going into their country (the U.S. doesn’t tax them) or to build a massive military complex in the middle of the South China Sea? I don’t think so!” Trump wrote in two consecutive tweets sent at about 5:30 p.m.

While the second part of the Trump tweet seemed to be talking about an artificial reef the Chinese have built in the South China Sea that can support a military base, it was not clear what Trump was referring to when he wrote about a possible request by China to devalue their currency.

The president-elect has accused the Chinese in the past of currency manipulation.

“China is the big abuser,” Trump said during the campaign, calling Beijing and other nations “grand masters at monetary manipulation.”

The tweets came after China lodged a complaint with the US on Saturday because Trump accepted a congratulatory call from the leader of Taiwan.

The call broke nearly 40 years of protocol, in which US presidents have not spoken directly to Taiwanese leaders, since China considers Taiwan to be part of its nation.

China was quick to respond to Trump’s call with the leader of Taiwan:

The tweets also came after a busy flurry of tweets by Trump, which began early Sunday with him warning that US companies moving their factories to Mexico will face “retribution” under his administration.

Fresh off his pre-inaugural victory in keeping 1,000 Carrier jobs in Indianapolis, Trump reiterated a campaign pledge to slap goods imported from Mexico with a 35 percent tariff.

“The U.S. is going to substantialy [sic] reduce taxes and regulations on businesses, but any business that leaves our country for another country fires its employees, builds a new factory or plant in the other country, and then thinks it will sell its product back into the U.S. without retribution or consequence, is WRONG!,” the president-elect tweeted in the 6 o’clock hour.

Such a tariff would require congressional approval, but House Speaker Paul Ryan previously fretted that Trump’s idea would start a “trade war,” with other countries imposing retaliatory higher taxes on US imports.