1. Gary Cohn is out: President Donald Trump's top economic adviser is leaving the White House, and his departure is sending shock waves through Wall Street.

Cohn, the former president of Goldman Sachs (GS), was a moderating voice in Trump administration, helping to temper more aggressive views on economic policy and especially trade.

US stock futures were down about 1% on Wednesday.

Cohn had been trying in recent days to soften Trump's plan to impose tariffs on aluminum and steel, which many observers fear could spark a trade war.

Global markets also reacted badly to the resignation. European stocks dropped in early trading, with many key indexes down by about 0.5%. Losses exceeded 1% in some Asian markets.

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2. Europe responds: The European Commission will brief reporters on Wednesday on how it will respond to Trump's steel and aluminum tariffs.

Commission President Jean-Claude Juncker said last week that Harley-Davidson (HOG) motorbikes and bourbon whiskey could be targeted.

It's also a big day for Brexit.

The European Union will also publish a draft proposal outlining plans for its future trading relationship with Britain. Separately, UK Treasury chief Philip Hammond will outline his view on the future of financial services.

3. Earnings and economics: Abercrombie & Fitch (ANF), Casey's General (CASY) and Dollar Tree (DLTR) will release earnings before the open. Caesars Entertainment (CZR), Costco (COST) and Rosetta Stone (RST) will follow after the close.

The US Census Bureau will publish January trade balance data at 8:30 a.m. ET. The Federal Reserve will release its Beige Book at 2 p.m., giving an overview of economic performance across the country.

4. Stock market movers -- Autodesk, H&R Block, Rolls-Royce: Shares in Autodesk (ADSK) and H&R Block (HRB) surged in extended trading after reporting better-than-expected quarterly results.

Shares in industrial conglomerate Rolls-Royce (RYCEY) jumped by 14% in London after the company released its annual results.

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5. Coming this week:

Wednesday — Costco (COST), Dollar Tree (DLTR) earnings
Thursday — Kroger (KR) earnings; Trans-Pacific Partnership Agreement set to be signed in Santiago de Chile
Friday — US monthly jobs report