The dollar rallied on Thursday after a report showed the U.S. economy created more private sector jobs than expected in May.
Panelbase said Prime Minister May's lead over the Labour Party increased to 15 points, giving the pound some respite from a plunge.
The dollar fell against most currencies on Tuesday, weighed by a drop in U.S.
Britain's pound was the only substantive mover among major currencies on Monday.
The dollar rose to a one-week high on Friday after upbeat U.S. gross domestic product data while Britain's pound slipped.
The Canadian, Australian and New Zealand dollars all fell solidly on Thursday, tracking a drop in oil prices.
The dollar was on the defensive on Thursday, with investors low on incentives to buy the greenback.
The dollar struggled to recover ground against other major currencies on Tuesday.
The dollar slipped to a more than six-month low against a basket of currencies on Monday.
The dollar was on track to record its worst week since August on Friday, having given up almost all the gains made since Trump was elected.
The U.S. dollar rose against a basket of major currencies on Thursday.
The yen rose to its highest in two weeks and the Swiss franc hit a seven-week high against the U.S. dollar on Wednesday.
The euro surged more than 1 percent against a broadly weaker dollar on Tuesday, rising above $1.10.
The Canadian dollar hit its highest level in two weeks and the Australian dollar was at a 10-day high.
The U.S. dollar fell on Friday, easing from a roughly two-month high against the yen.
The New Zealand and Canadian dollars sank on Thursday as domestic concerns outweighed a bounce in oil prices for the currencies.
Trump abruptly fired FBI Director James Comey in a move that shocked Washington and dampened some of this week's strong risk appetite.
Currency markets swung back to trading on the diverging outlooks for growth and tighter monetary policy.
Meanwhile, a fall in oil prices drove the Australian dollar and Canadian dollar to new lows.
Investors took profit on a roughly 3 percent gain for the currency since the first round of voting two weeks ago.