(Reuters) - U.S. stock index futures tumbled on Monday as fears of a full-blown trade war and its impact on the global economy jolted markets around the world after President Donald Trump levied steep tariffs on Mexico, Canada and China.

Over the weekend, Trump imposed hefty new tariffs of 25% on imports from Mexico and Canada, and 10% on China - which he said may cause "short-term" pain for Americans.

"Breaking global trade may seem like the thing to do to resurrect the US industrial economy, a noble ambition, but, break trade and you disrupt global capital flows necessary to finance the US budget deficit," an analyst at GlobalData.TS Lombard wrote in a note.

Trump said he would talk on Monday with the leaders of Canada and Mexico, which have announced retaliatory tariffs, but downplayed expectations that they would change his mind.

The iShares MSCI Mexico ETF lost 2.4% in premarket trading, while an ETF tracking Canada slipped 2.8% in light volumes.

At 04:11 a.m. ET, Dow E-minis were down 588 points, or 1.32%, S&P 500 E-minis were down 94.25 points, or 1.55%, and Nasdaq 100 E-minis were down 402.25 points, or 1.86%.

Futures linked to the economically-sensitive Russell 2000 smallcaps index slumped more than 2%.

Most chip stocks slumped, with industry bellwether Nvidia sliding 3%, while Broadcom lost 3.4%.

Most megacap growth stocks also slid, with Apple and Microsoft down close to 2% each.

Legacy automakers Ford dropped 4.1%, while General Motors shed 6.7%.

Trump also warned that tariffs on Europe will "definitely happen", but did not offer any clarity over his plans. The pan-European STOXX 600 was last down 1.4%. [.EU]

Goldman Sachs noted that if said tariffs are sustained, it could reduce their S&P 500 earnings per share (EPS) growth forecast by roughly 2%-3%, while Morgan Stanley also expects US equities to come under pressure.

Treasury yields eased a touch as investors moved into safer assets such as bonds, while the dollar index was last flat.

Meanwhile, the quarterly earnings remain in full swing, with Google-parent Alphabet, chipmaker AMD, payments platform PayPal and drugmaker Eli Lilly some of the prominent companies reporting earnings this week.

Of the 178 companies in the S&P 500 that have reported earnings so far, more than 75% reported earnings that beat analyst estimates, as per data compiled by LSEG.

Later in the day, a January manufacturing activity reading is expected. The January non-farm payrolls report is also due this week on Friday.

Among other movers, cryptocurrency and blockchain-related stocks dropped as bitcoin prices tumbled in a global risk-off move.

Exchange operator Coinbase dropped 5.7%, while the largest corporate holder of bitcoin, MicroStrategy, slid 5.2%.

The ProShares Bitcoin ETF lost 5.6%.

(Reporting by Shashwat Chauhan in Bengaluru; Editing by Shinjini Ganguli)