Stock futures were tumbling Tuesday as investors fretted over President Donald Trump's plan to impose tariffs on eight NATO countries until they let his administration acquire Greenland.

These stocks were poised to make moves:

Chip designer Nvidia dropped 2.8%, Google owner Alphabet fell 3.5%, and iPhone maker Apple slid 1.6% ahead of the opening bell as souring risk sentiment had investors ditching mega-cap tech stocks. Fellow Magnificent Seven members Microsoft, Amazon, Meta Platforms, and Tesla also were trading in the red. Broadcom and Berkshire Hathaway, the two other U.S. companies with valuations of over $1 trillion, fell 2.8% and 0.8% respectively.

AppLovin tumbled 11%, making it the S&P 500's biggest loser in premarket trading. There's no reason why tariffs would be a blow for the advertising software developer -- but its shares have taken a battering this year, slumping amid a broader tech selloff. AppLovin stock was on course to extend a four-day losing streak, which started last Tuesday. It has declined 23% over the span.

Crypto stocks also dropped as investors dumped risk-on assets like Bitcoin, which has fallenn 2.2% over the past 24 hours to $90,984. Digital-asset exchange Coinbase Global fell 4.4%, online trading platform Robinhood Markets slid 4.2%, and major Bitcoin investor Strategy plunged 5.1%.

Pockets of the market were doing well, though. Shares in global packaging company Amcor and gold miner Newmont rose 3.3%, making them the S&P 500's two best performers. The rally in Newmont shares came as investors pivoted to safe-haven assets, with gold futures surging 3.1% on Tuesday.

RAPT Therapeutics jumped 64% to $57.37. Pharma giant GSK said on Tuesday that it had agreed to buy the biotech for $58 a share, or an estimated aggregate equity value of $2.2 billion.