An independent Scotland would play a positive and co-operative role in the European Union in contrast to the often sullen, disengaged stance adopted by successive UK governments, Alex Salmond claimed.
The Scottish First Minister said Britain is now at the "margins of European influence", and warned against the "rising influence of a virulent strain not just of Euroscepticism, but of Europhobia" in the UK.
Mr Salmond used a speech in Bruges, Belgium, today to argue that being part of the UK had had a damaging impact on Scotland, but independence would allow the country to "contribute as equals" in Europe.
The First Minister said: "An independent Scotland, as an equal member state, will bring a positive, co-operative voice to the EU, in contrast to the often sullen, disengaged voices that have spoken on our behalf since Margaret Thatcher's speech in this city more than a quarter of a century ago.
"Not being at the top table in Europe has harmed Scotland's interests for four decades. Within the UK, we are occasionally consulted. With independence, we would contribute as equals. And in contributing as equals, we would make proposals to address the democratic challenges that Europe faces today."
Scotland's membership of the EU has been a key issue in the run up to the referendum, with those who are opposed to independence arguing it would not be able to negotiate the same deal that the UK currently enjoys, including its opt-out on the euro currency.
Foreign Secretary William Hague has insisted: "Scotland's negotiations to join the EU are likely to be complex and long and the outcome would certainly prove less advantageous than the status quo.
"People in Scotland deserve to have the available facts ahead of making one of the most important political decisions in the history of our union."
Mr Salmond said the Scottish Government recognised "continued membership of the EU will require negotiations on the specific terms", adding that is "only right and proper".
But he insisted those negotiations would be completed in the 18 months between the referendum and March 2016, when it is proposed Scotland would become independent if there is a Yes vote.
The First Minister told academics and students in Bruges that an independent Scotland would be "an enthusiastic, engaged and committed contributor to European progress".
He spoke about the "rising influence of a virulent strain not just of Euroscepticism, but of Europhobia at Westminster" and warned this "poses a real threat to Scotland's place in Europe".
Mr Salmond said: "Every single one of the four prime ministers since Margaret Thatcher has pledged to put Britain 'at the heart of Europe'. Yet the reality has been quite different. Today Britain sits at the margins of European influence, and if Scotland remains governed from London, we face the prospect of an in-out referendum on whether to be part of the European Union at all."
While he said people in Scotland would "almost certainly vote to stay in the EU", the First Minister added that the result for the UK as a whole would be "much more doubtful".
He went on: "Because Scotland makes up just over 8% of the UK population, it is conceivable that unless we choose to change our circumstances this September, we could be dragged out of the European Union against our will."
Mr Salmond insisted the "real risk to Scotland's place in the EU" was not independence, but the in-out referendum on European membership proposed by the Tories for of 2017.
He added that an independent Scotland would adopt a "practical, common sense approach to membership, which means that there is no detriment - none whatsoever - to any other member of the European Union as a result of Scotland's continuing membership"
The First Minister continued: "Scotland's vast natural resources and human talent make it one of the lynchpins of the European Union. We have a key role to play in providing energy security for Europe. As one of the wealthiest countries, Scotland is a net financial contributor to the EU and will remain so as an independent member. We have more top universities, per head, than any other member of the EU and our academics collaborate with partners across Europe. We have one of the largest national shares of Europe's total fishing grounds. The EU's fisheries policy would unravel without Scotland."
He said Scotland wants to "contribute to the future success of the European project from which we gain so much", and insisted: "When our small nation asks for the freedom to contribute, we will meet a welcome from around Europe.
"And we will gladly make those contributions - and more - when an independent Scotland, takes its full place in the European family of nations."
But Ian Duncan, a Scottish Conservative candidate for next month's European elections, said: "The First Minister is completely failing to see the issue of EU membership through any eyes but his own. He isn't considering what other countries will want in return for granting membership.
"It is abundantly clear, even from this speech, that a vote for separation in September is a vote for uncertainty."