U.S. stock benchmarks on Tuesday afternoon finished at fresh records, with the S&P 500 and Nasdaq registering a sixth straight gain for 2018. The three main equity benchmarks have gained between 21% and 30% over the past 12 months, supported by factors such an expanding global economy, growth in corporate profits and enthusiasm over the Trump administration's tax cuts.

U.K. stocks closed higher Tuesday, with the blue-chip index setting another record as Wm. Morrison Supermarkets PLC helped lead gains in retail shares following its upbeat Christmas sales update.

Some Asian stock markets pulled back Wednesday morning, ending a big start to 2018 for global equities, though Hong Kong's benchmark climbed to a 10-year high.