US stock futures fell on Friday after China announced it will raise tariffs on US imports from 84% to 125%, escalating tensions just days after US President Donald Trump's sweeping trade measures.

At 4:35 am ET, the Dow Jones lost 135 points or 0.34%, the Nasdaq 100 fell 0.43%, and the S&P 500 declined 0.36%.

In currency markets, the euro was up by 1.89% against the dollar at 4:36 am ET, selling for $1.14106.