LONDON (AP) — The British pound slipped sharply after an opinion poll showed that those advocating Scottish independence from the United Kingdom have gained ground, a little more than two weeks before the vote.

A YouGov poll released Tuesday showed the “no” lead at only six percentage points. Less than a month ago, the equivalent poll lead was over 20 points. The narrowing echoes other findings that the “yes” campaign has gained ground over the past week or so.

It also spooked some traders, and the pound traded 0.6 percent lower at $1.6525.

Kathleen Brooks, research director at Forex.com, says there are signs “the tide is starting to shift” and that the prospect of independence “could boost volatility” in the pound in the coming weeks.

The Scottish independence vote takes place Sept. 18.

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