PERTH, United Kingdom (AFP) - Scotland's First Minister Alex Salmond will step down as leader of the Scottish National Party (SNP) at its annual conference on Friday after Scots voted against independence in September.

The head of the party for nearly 20 years and first minister for seven years, Salmond had his last parliamentary questions session on Thursday as he retires from the political frontline.

The SNP conference is taking place on Friday and Saturday in the city of Perth, north of Edinburgh, and his successor as head of the party will be 44-year-old Nicola Sturgeon.

Salmond will be remembered as the man who gave Scotland its first independence referendum but then lost, with 45 per cent against 55 per cent voting in favour of Britain staying united.

Salmond announced his resignation after the results of the Sept 18 vote were announced but said he would stay on in the regional parliament, representing his local constituency.

The SNP's membership has swelled since the referendum from 25,000 before to 80,000 now.

Many people in Scotland are disillusioned with perceived failures by the government to press ahead with plans to grant the territory more autonomy.

Sturgeon is expected to be voted in as first minister next week by the SNP-dominated regional parliament.