Oil prices today tumbled after U.S. President Donald Trump said he would sharply raise tariffs on Chinese goods this week, risking the derailment of trade talks between the world's two biggest economies.<br />'' <br />''<span style="color: #222222;">Brent crude prices, in intraday trade, were trading around 70 dollars and 60 cents per barrel. WTI prices were at around 61 dollars and 50 cents per barrel when reports last came in.    </span><br />