FORMER Prime Minister Gordon Brown has turned Labour's pro-UK campaign launch into an anti-Tory tirade by accusing David Cameron's Government of going down an Enoch Powell-style route over immigration.

Mr Brown, who made a rare public appearance to take the keynote role in the launch of United With Labour in Glasgow, switched his guns from Alex Salmond to the Prime Minister in criticism of his response to the UK Independence Party.

Mr Brown likened the current stance of the Conservative-led coalition to Enoch Powell and his infamous "rivers of blood" speech of 1968 while also mocking their relationship with Ukip in an echo of Margaret Thatcher's famous "the lady's not for turning" address.

Mr Brown accused the Conservatives of having nothing positive to say about the Union because of its obsession with the EU, which he said was "driven by Ukip".

He added: "A party which was once pro-Europe is now anti-Europe, a party which was once anti-Powellite on immigration is now becoming very close to being Powellite on that issue.

"On almost any issue, you can see the Conservative Party doing U-turns.

"U-turns on alcohol prices, U-turns to legislate on overseas aid, U-turns on gay marriage. I suppose the new term isn't U-turn, it's Ukip-turn. I say to the Conservatives, Ukip if you want to, we're going to stick to what we believe in."

In his first major Labour Party speech since leaving Downing Street in 2010, Mr Brown also reflected on his loss of office, saying he had time to think about the "courtesy of the British people".

He said he now wanted to "put the positive, principled, forward-looking case for a strong Scottish Parliament inside a strong United Kingdom".

However, Angus Robertson MP, SNP spokesman at Westminster, said Mr Brown's comments had undermined the case for the No campaign.

Meanwhile, Deputy First Minister Nicola Sturgeon said: "Is it more or less likely that a government elected in Scotland will reflect the views and priorities of the Scottish people better than a remote government in Westminster that is all too often elected against the clear wishes of Scotland?"

Mr Brown said he wanted to put the case for the pooling and sharing of resources right across the UK, highlighting the benefits of UK pensions, national insurance, healthcare funding and the minimum wage.

He said: "There are equal social, political and economic rights for people no matter which community you live in, no matter whether you are in a poor area or a rich area of the country. I could put the case for the Union by talking about how our defence needs are common, our security needs are mutual, our environmental concerns are shared, that we are part of one single island.

"But I want to make the case, the most modern case for the Union, for the pooling and sharing of resources so that we are in a position to tackle poverty, unemployment together."

However Mr Robertson said Mr Brown's comments summed up the "fundamental flaw" at the heart of the No campaign's case.

He said: "Despite his attacks on the Tories, Gordon Brown's impossible position is that decisions about immigration, welfare and European policy in Scotland should all be taken in Westminster by these same Tories – who are being dragged to the right by their fear of Ukip, and doing so much damage to Scotland's interests."