The trade war looks to be back on in a big way after a series of pronouncements from President Trump and the White House.

The latest: Trump told reporters in London Tuesday he had "no deadline" for a China deal and that he liked "the idea of waiting until after the election for the China deal."

That followed an early Monday announcement that the U.S. would reimpose tariffs on steel and aluminum imported from Brazil and Argentina for "presiding over a massive devaluation of their currencies."

U.S. stocks predictably performed poorly, with the S&P 500 closing 0.9% lower and the tech-heavy Nasdaq dropping 1.1%.

"Trump’s tweets suggest a failure to understand how trade flows, exchange rates, or economies function at the most basic level," Karl Schamotta, chief market strategist at Cambridge Global Payments, told Axios.

Hours after Trump's Monday morning tweet, Commerce Secretary Wilbur Ross said on Fox Business that December was a "really good time" to add more tariffs to Chinese imports because it wouldn't "interfere with this year’s Christmas."

Ross also noted that time was running out to secure a trade deal before the next round of tariffs kick in on Dec. 15.

Later in the day, the USTR issued a statement saying it was "initiating a process to assess increasing the tariff rates and subjecting additional EU products to the tariffs,” and claiming the EU didn’t sufficiently eliminate the adverse effects of its subsidies to Airbus.

To top it off, Trump’s chief trade negotiator Robert Lighthizer yesterday suggested adding tariffs of 100% on $2.4 billion of French imports like cheese, sparkling wine and makeup. This was in response to an investigation that concluded a French digital services tax discriminated against U.S. internet companies.

On the other side: Chinese officials have continued to slow roll and push back on the "phase one" trade deal. Late Monday, China said they would soon publish a list of “unreliable entities” that could lead to sanctions against American companies.

France's finance minister said the European Union would "be ready to retaliate” if the U.S. imposed the tariffs on its products.

The big picture: “Markets have had a great run this year and expectations are already high that a trade deal gets done,” David Carter, chief investment officer at Lenox Wealth Advisors, told Reuters.

“The most recent tariff tweet has reminded markets that there’s a lot of uncertainty around trade policy and U.S. actions."

The bottom line: The day's actions "ought to make a whole lot of people nervous,” William Reinsch of the Center for Strategic and International Studies told the Washington Post. “It kind of makes people wonder what’s the point of negotiating if this is going to happen.”

A good day for steel

Expand chart Data: Money.net; Chart: Andrew Witherspoon/Axios

While the broader market suffered, shares of U.S. steel companies got a big boost from the president's Monday morning tweet.

Yes, but: It's been a rough year for the American steel industry. Both TimkenSteel and U.S. Steel have lost around a third of their share price year to date and while AK Steel shares have risen on the year, they are around 80% below their 2017 peak.

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