The British pound is posting strong gains after another opinion poll indicated that those advocating a British exit — so-called Brexit — from the European Union are losing ground.

With less than a month to go before the June 23 referendum on Britain's EU future, a string of polls are showing the "remain" camp building up a sizeable lead.

On Tuesday, a telephone poll for the Daily Telegraph newspaper conducted by ORB, showed the "remain" camp at 55 percent against 42 percent for the "leave" campaign. The poll of 800 people took place May 18-22 but gave no margin of error.

Hopes that Britain will remain in the EU saw the pound rise 0.7 percent to $1.4586. Concerns over a potential British exit have weighed on the currency this year.