FACTBOX-Scottish National Party policies

(Reuters) - Scottish nationalists say that if they win control of the parliament in Edinburgh in Thursday's election and form a coalition, they will hold a referendum on independence within four years.

Here are some of the aims of the Scottish National Party (SNP).

-- Full Scottish independence. The current Scottish parliament established in 1999 has powers over health affairs, education, justice, rural affairs, and transport, but the British parliament controls the economy, taxation, defence and foreign relations, and can override the Scottish parliament.

-- An independent Scotland would invest a share of future oil revenues in a fund that could be worth almost 90 billion pounds ($180 billion) in 10 years, following a Norwegian model to benefit future generations, the SNP says.

-- Queen Elizabeth would remain head of state in Scotland.

-- An independent Scotland would retain the pound as its currency initially but may join the euro later.

-- SNP leader Alex Salmond announced in January that an SNP government would introduce a levy on Britain's Trident nuclear warheads transported through Scotland, hoping to deter London from basing any future nuclear weapons in Scotland.

Sources: Reuters/SNP Web site