Sterling advanced on Thursday as the campaign for Britain's vote on whether to leave the European Union was suspended following the murder of a British lawmaker, while US stocks cut losses.
British Member of Parliament Jo Cox, who was shot dead in the street in her constituency in northern England earlier in the day, had been a vocal supporter of Britain remaining within the European Union.
Whether Britain will leave the European Union, dubbed "Brexit," is an issue that will be decided in a referendum next week and could undermine decades of European integration and stoke global economic uncertainty.
"Certainly, people are talking about the possibility that this does influence the Brexit vote in favour of remain. It is a tragic event all around. There is a sense, there is an immediate emotional reaction, but there is still a week before the referendum itself" on June 23, said Alan Ruskin, global co-head of FX research at Deutsche Bank in New York.
The British Pound hit a US trading high after the news, and was last up slightly at $1.4207.
Rival referendum campaign groups in Britain said they were suspending activities for the day and Prime Minister David Cameron said he would pull out of a planned rally in Gibraltar, the British territory on the southern coast of Spain.
US stocks, which had tumbled earlier on global growth worries, cut losses and the Dow briefly traded higher.
The Dow Jones industrial average was up 17.67 points, or 0.1 per cent, at 17,657.84, the S&P 500 lost 2.41 points, or 0.12 per cent, to 2,069.09 and the Nasdaq Composite dropped 10.81 points, or 0.22 per cent, to 4,824.12.
The European FTSEurofirst 300 index closed down 0.5 per cent.
Oil prices slumped about three per cent and were down a sixth straight day as the Dollar's rally on fears of Britain's exit from the EU hammered commodities priced in the currency.
Data showing US crude stockpiles fell less than expected also weighed on oil prices. Brent crude futures were down $1.52 at $47.45, while US crude futures were down $1.61 at $46.40.
Yields on most US Treasury yields rose to session highs after British campaigning for the Brexit vote was suspended following MP Cox's death.
Yields on benchmark 10-year Treasury notes rose to a session high of 1.581 per cent, after earlier falling to 1.518 per cent, the lowest level since August 2012.