Coalition Environment Secretary Owen Paterson will today hold talks with his opposite number in the US Government in a bid to overturn a 40-year ban on the import of haggis.
However, Mr Paterson was accused by Scotland's Rural Affairs Secretary, Richard Lochhead, of taking up the issue only in response to September's independence referendum.
The row follows a similar spat between the Westminster and Holyrood administrations earlier this month over a bid to win protected status for Ayrshire tatties. The two governments have yet to fall out over neeps, however.
It came as a referendum row also overshowed the Armed Forces Day celebrations in Stirling on Saturday.
Prime Minister David Cameron was accused of attempting to politicise the event after saying Scotland enjoyed "the best of both worlds" as part of the UK during a visit to the event.
Mr Paterson will meet Tom Vilsack, the Secretary of Agriculture in Barack Obama's administration, in Washington to discuss the US ban on imports of British-produced lamb and sheeps' lung imposed in 1971.
Speaking ahead of the meeting, he said: "This Government has opened many markets for our home-grown food and drink businesses.
"I will continue to do everything I can to boost exports of everything from whisky to haggis to support Scotland's farmers and rural economy."
Alistair Carmichael, the Secretary of State for Scotland, added: "It seems only right that the UK Government continues to use its considerable influence to open up as many opportunities as possible, to reintroduce our produce where markets have been closed and to create new ones wherever it can."
The Scottish Government formally welcomed the move but claimed the UK Government was acting only in response to the referendum, in contrast to strenuous efforts by Holyrood ministers in recent years to keep the issue in the public eye and pressure the US to overturn the ban.
Mr Lochhead said: "The US has long been a top priority market for the Scottish food and drink sector.
"I have been pushing for this development for years - therefore I welcome Owen Paterson's efforts to open up this lucrative market, even if it's taken the forthcoming referendum to get his attention."
The UK haggis market is worth £15 million per year.
Producers believe the US market could be worth even more, given the country's interest in Scottish heritage and enthusiasm for Burns Night, by far the biggest day for haggis sales around the world.
The US banned imports in 1971 as part of a general ban on the sale of livestock lungs, an essential ingredient of traditional haggis.
Following the BSE "mad cow" crisis in the late-1980s, the import ban was extended to cover all UK - and later EU - red meat. The US recently agreed to drop its ban on beef imports raising hopes that sales of sheep products would also be restored.
Import/export restrictions are easing as a result of a major EU-US trade deal, the Transatlantic Trade and Investment Partnership (TTIP), which is currently being negotiated.
The deal is potentially worth more than £10 billion to the UK economy overall.
The haggis row follows angry clashes earlier this month over efforts to win EU protected status for Ayrshire Earlies, the unique new potatoes grown around Girvan for nearly 200 years.
Both the UK and Scottish Governments sought to claim credit for the initiative which, if successful, would give the tatties the same protected status as Arbroath Smokies, Stornoway Black Pudding and Scottish Salmon.
Meanwhile, David Cameron came under fire for using Armed Forces Day to argue for Scotland to remain in the UK.
The Prime Minister paid tribute to military personnel and their families as more than 35,000 people watched a parade, fly past and series of displays.
But he added: "My message is always that Scotland get the best of both worlds and that's what we want to see.
"More power through the Scottish Parliament to make its own decisions but also the benefit of being part of a larger United Kingdom with - one advantage - these armed forces which can help protect our values and keep us safe."
SNP defence spokesman Angus Robertson said: "It was a massive error of judgment - I don't think our service men and women, and veterans who ever they support in the referendum will be very impressed.
"It's disrespectful, for example, to 101-year-old veteran Jimmy Sinclair - the last surviving Desert Rat - who is backing independence and 92-year-old D-Day veteran Peter McColl who met with the First Minister yesterday and has been a member of the SNP since 1947.
"He is living for September the 18th."
Meanwhile, former LibDem Scottish Secretary Michael Moore has called for the pro-UK parties to unite around a new devolved package of welfare and employment powers quickly after the independence referendum in the event of a No vote. Mr Moore said: "Scotland is going to be a very different political place after the referendum than the one we have been used to for the last 15 years, and the debate about more powers is becoming just as important as the debate about independence."