US inflation remains stubborn

The U.S. consumer price index rose 0.5 percent in January, an increase of 6.4 percent year-on-year, according to the U.S. Bureau of Labor Statistics.

Meanwhile, the so-called "core inflation," which excludes

energy and food prices, saw a 0.4 percent rise month-to-month and 5.6 percent increase from the same period last year.

The U.S. Federal Reserve has been engaged in an aggressive rate hike cycle to tamp down the worst inflation in decades.