Chief Secretary to the Treasury Danny Alexander has warned the economic recovery is threatened by a Yes vote in September.
Figures released yesterday showed that the UK GDP returned to its pre-recession level in the second quarter of the year.
According to the Office of National Statistics, the economy is now worth 0.2% more than at its peak in 2008.
Mr Alexander, Liberal Democrat MP for Inverness, Nairn, Badenoch and Strathspey, called the improvement “fantastic news for the UK, Scottish and Highland economies”.
He said: “We are seeing strong growth which has brought our economy back to pre-recession levels. This is only possible due to the hard work of thousands of companies, millions of workers and a UK government determined to stick to our economic plan that gives business confidence to invest.
“Jobs are being created in every sector and in every part of Scotland, no more so than in the Highlands which is one of the strongest performing regions of the UK.
“It is vitally important that we steer clear of separation so the hard won recovery is not put at risk. By staying with the UK we can ensure that the recovery stays in the fast lane.”
Finance Secretary John Swinney said Scotland moved above its pre-recession level in the first quarter of the year.
“Today’s figures confirm that Scotland has been ahead of the UK when it comes to achieving pre-recession output,” he said.
“We also have the fastest annual growth in over three years, we are outperforming the rest of the UK on jobs, with employment and economic activity at an all-time record, and inward investment to Scotland is now booming at a 16-year high.
“All of this confirms the underlying strength and diversity of Scotland’s economy.”
Mr Swinney did not comment on the implications of economic improvement to the independence debate.
But his spokesman said: “Scotland is one of the wealthiest countries in the world – but the Tory Westminster policies backed by Danny Alexander mean it doesn’t feel that way for many people.
“Only a Yes vote in September will mean Scotland’s wealth in Scotland’s hands, creating a more prosperous nation and a fairer society.”