ABERDEEN, Scotland - Scottish leader Nicola Sturgeon will accuse Prime Minister David Cameron of playing 'fast and loose' with Britain's place in the European Union on Saturday, criticising his renegotiation strategy before a public vote on remaining an EU member.
Britain's future in Europe has become a defining issue for the country. Cameron has promised to negotiate new membership terms before holding a referendum by the end of 2017 on whether to leave the EU.
A vote to leave would have profound consequences - among other things, it might trigger a fresh bid for Scottish independence by the pro-EU Scottish National Party, threatening to end the 300-year-old union of Scotland and England.
Sturgeon, who supports the European Union but eventually wants Scotland to become an independent country, will use a speech at her Scottish National Party's annual conference in Aberdeen to criticise Cameron's handling of the issue.
"We despair at the failure of leadership of a prime minister pandering to Eurosceptics in his party, but unable to articulate clearly and precisely what it is he is seeking to renegotiate," Sturgeon will say, according to advance extracts of her speech.
Earlier this week, Cameron sought to defuse the frustration of fellow EU leaders over lack of detail in his renegotiation demands by promising to send them a list of proposals in writing in early November.
Sturgeon will use the speech to her party faithful to spell out her unwavering support for the EU, regardless of whether Cameron is successful.
"David Cameron might play fast and loose with our place in Europe, but be in no doubt - the SNP will campaign positively for Scotland, and the UK, to stay in the European Union," she will say
Opinion polls show public opinion across the whole of Britain is narrowly in favour of remaining a member of the EU. It is higher among Scotland's voters.
Sturgeon has listed a vote to leave the bloc as something that would almost certainly spark a fresh referendum on Scotland's independence - an issue that has gathered steam even though Scottish voters rejected breaking away last September.
Support for the SNP surged following that vote, but Sturgeon has played down the prospect of another referendum in the near future, focussing instead on next May's elections to the Scottish parliament.