ALEX Salmond will make a series of speeches on Scottish independence during a week-long trip to the US.

The First Minister flies out to the US tomorrow for the annual Tartan Week celebrations in New York and Washington.

He will discuss the "economic viability and credibility of an independent Scotland" in a speech to the Carnegie Council for Ethics in International Affairs in New York on Friday.

A day later he will deliver a public lecture titled The Wealth and Well-being of Nations at Princeton University. In a third high-profile speaking engagement next Tuesday, at the Brookings Institution think-tank in Washington DC, the First Minister will explain the "values and principles that would shape a modern, independent Scotland".

The plans have angered MSPs from the pro-UK parties. However, the Scottish Government insisted the visit was "economy focused".

Mr Salmond will also hold meetings with potential business investors and help launch VisitScotland's Homecoming 2014 tourism drive in the States.

The visit is the first Mr Salmond has made in five years to mark Tartan Week, as the celebrations are known in the States.

Events include a fashion show, arts events and a parade of pipebands along New York's Sixth Avenue on Saturday, April 6, the day recognised in the US as Tartan Day.

Mr Salmond will be the guest of honour at the annual Tartan Day reception at the US Capitol.

In addition to the First Minister's trip, Transport Minister Keith Brown is travelling to Canada for a number of Tartan Week engagements starting this week.

The Scottish Government's budget for "Scotland Week" – as it has badged its own events in recent years – is £360,000. However, that does not include the cost of a separate Scottish Parliament delegation led by Presiding Officer Tricia Marwick.

The First Minister said he would be "setting out Scotland's ambition to enter the global community of nations" when he unveiled parts of his itinerary last week.

But MSPs from the pro-UK parties claimed he should not use the visit to promote independence.

James Kelly, Scottish Labour's chief whip, said: "The First Minister should be representing Scotland's interests when he is abroad, not the SNP's. Alex Salmond should be using this trip to talk about investment and jobs, not bang the drum for independence at the taxpayers' expense. Yet again, his priorities are all wrong."

Scottish Conservative chief whip John Lamont said: "The separation of Scotland from the rest of the UK should not be the priority business for the taxpayer-funded Scottish Government. When the First Minister embarks on these jollies, the least he could do is try to promote trade and tourism.

"Instead, he will spend his time drumming up US support for independence, no doubt at the cost of thousands of pound to the hard-pressed public purse."

A Scottish Government spokeswoman said: "The First Minister and Transport Minister Keith Brown will attend Scotland Week to promote Scotland on the world stage, undertaking a series of business and tourism engagements in the US and Canada respectively.

"The budget for Scotland Week 2013 has been capped at £360,000, which is less than previous Scotland Weeks and substantially less than the costs of earlier Tartan Weeks. Final costs will not be known until the programme is completed."