US President Donald Trump (R) and China's President Xi Jinping (L) along with members of their delegations, hold a dinner meeting at the end of the G20 Leaders' Summit in Buenos Aires, on December 01, 2018.

President Donald Trump said in a tweet on Friday that trade talks with China "are going very well" but investors hardly reacted to his exuberance.

@realDonaldTrump: China talks are going very well!

The Dow Jones Industrial Average moved slightly higher following the president's tweet.

Trump also tweeted on Thursday night a "statement from China," saying: "The teams of both sides are now having smooth communications and good cooperation with each other. We are full of confidence that an agreement can be reached within the next 90 days."

U.S. stocks have been battered this week, with the Dow and S&P 500 indexes each falling 2.3 percent.

Trump's meeting with Chinese President Xi Jinping last weekend gave investors optimism on Monday that some progress was being made in trade negotiations.

But the positive bump to stocks from the "trade truce" didn't last long. The bond market began sending signals of an economic downturn on Monday afternoon. Then, on Tuesday, Trump declared himself "Tariff Man" in a tweet. He threatened to heighten the trade war with China by adding tariffs if negotiations fail. Trump's statements gave investors little hope that progress had been made on trade negotiations.

Additionally, Dow futures went tumbling overnight Wednesday after Canada's Department of Justice announced it arrested Huawei CFO Meng Wanzhou. Made at the request of U.S. authorities, Meng's arrest was a shock to Beijing – the latest blow to the "trade truce."

This is a developing story. Check back for updates.

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