LONDON: Europe's stock markets opened mixed on Wednesday before a US interest rate decision, with London dipping on data showing UK inflation spiked to its highest level for more than a decade.

The British capital's benchmark FTSE 100 index slipped 0.1 percent to 7,208.75 points after news that UK inflation rocketed to 5.1 percent in November on broad-based price gains.

On the upside, the Paris CAC 40 index added 0.6 percent to 6,935.51 points, and Frankfurt's DAX index rose 0.4 percent to 15,519.39.

Pressure is mounting on central banks around the world to act in order to get a grip on runaway inflation, which has been sent soaring this year by a spike in energy prices, long-running supply chain snags and surging demand.

The Federal Reserve is expected later on Wednesday to announce a speedier withdrawal of its massive financial support just as the Omicron variant fans concerns about the economic recovery.

The announcement will be followed by rate decisions from both the European Central Bank (ECB) and the Bank of England on Thursday.

The BoE is however forecast to hold its record-low interest rate, despite rampant inflation, as policymakers fret over Omicron fallout.