US rate guesswork weighs on stock markets

Stock markets across the world dipped Monday as investors tried to second-guess the US Federal Reserve on the timing of its next interest rate hike. In a much-scrutinized speech, Fed chief Janet Yellen on Friday hinted at a US interest rate rise by the end of the year. Yellen said a pick-up in the world's top economy and an improvement in the jobs market meant "the case for an increase in the federal funds rate has strengthened in recent months".