Whisper it, but the next challenge for financial markets and policymakers may not be deflation, but the remarkable surge in oil prices from the six-year low touched in January. Since then, Brent crude futures have risen 45 percent. These measures have ranged from interest rate cuts to bond-buying “quantitative easing” programmes. All have been in response to the fall in inflation rates and inflation expectations driven by the 60 percent collapse in oil prices over the latter part of last year.