Regional airports in the rest of the UK must be helped to avoid "uncertainty and risk" caused by handing the Scottish Government control over Air Passenger Duty (APD) rates, Labour has urged ministers.

Shadow chancellor Ed Balls warned that failing to introduce a mechanism to prevent them being undercut by rivals north of the border could be a breach of the Smith Commission's principle that devolution should not adversely affect other parts of the UK.

The Scottish National Party administration at Holyrood wants initially to halve and eventually abolish APD but the agreement to grant Scotland the freedom to set its own rate has raised fears in cities such as Newcastle and Manchester.

Willie Walsh, chief executive of British Airways' parent company IAG, said people would be "rushing across the border" as a zero rate would make it £276 cheaper for a family of four to fly to the US.

He joined a chorus of industry calls for APD to be scrapped across the UK.

In a letter to Chancellor George Osborne, Mr Balls reminded him of the agreed principle that implementation of devolution should "not cause detriment to the UK as a whole nor to any of its constituent parts" and "cause neither the UK Government nor the Scottish Government to gain or lose financially simply as a consequence of devolving a specific power.

"It is important that, in implementing the Smith recommendations in relation to Air Passenger Duty, this principle is upheld," read the letter, also signed by the shadow transport and business secretaries and copied to their cabinet counterparts.

"This means ensuring that English regional airports are not disadvantaged,"

"English regional airports cannot be faced with continuing uncertainty and risk through not knowing whether they will be significantly disadvantaged should a future Scottish Government introduce changes to Air Passenger Duty.

"It is therefore imperative that the UK Treasury leads work across Government - and working with the Scottish Government - on a mechanism to ensure that English airports, particularly in the North of England, are not disadvantaged.

"We would be grateful for confirmation that this work is under way."

Sedgefield MP Phil Wilson suggested regions could be afforded flexibility to set their own rates.

Asked about specific solutions, a Labour source that the Opposition "will be constructive about whatever solutions the Government comes up with."

Mr Walsh said: "APD must be axed across the UK - not just in Scotland - to avoid a domino effect across the country.

"Removing Scottish APD would see passengers rushing across the border to avoid paying the punitive tax at Newcastle, Manchester or any other English airport. Who could blame them - a family of four flying to the US would save £276 in APD by heading north.

"It's understandable why the SNP wants to cut APD - it costs Scotland £200 million each year in tourism alone. Economic analysis shows that scrapping APD across the UK would bring an immediate 0.5% boost to GDP and lead to 60,000 new jobs.

"After 20 years of fleecing passengers, this tax has lost any economic credibility".

Darren Caplan, chief executive of the Airport Operators Association (AOA), said: "UK levels of Air Passenger Duty (APD) continue to be the highest in the world, and represent a growing barrier to trade, investment and tourism.

"The AOA supported the Treasury's removal of APD for the longest flights in the 2014 Budget, but the fact remains that at a time when our international competitors are either freezing or abolishing their respective air taxes, overall levels of APD in this country are still at record high levels, and are increasing year after year.

"A cut in APD anywhere should be matched by a cut everywhere in the UK. The AOA will continue to make this case to the Treasury in the months ahead."

Travel organisation Abta said: "Any inconsistencies between what a passenger pays flying from Scotland compared to elsewhere in the UK could create an uncompetitive and damaging situation for travel businesses.

"Abta has welcomed that the Scottish Government has recognised the damaging impact this tax is having on jobs and growth as well as on consumers. In light of today's announcement, Abta is urging the UK Government to review the level and impact of this damaging tax with a view to reducing it across the whole country."

Board of Airline Representatives (BAR UK) chief executive Dale Keller, representing 74 airlines, said: "The Scottish Government has already indicated it would slash or scrap the world's highest air passenger tax to stimulate the local economy. The right time is now for the whole of the UK to share equally in the benefits a phasing out of APD would deliver."

First Minister Nicola Sturgeon told a press briefing at Holyrood: "We said in the white paper we would want to start by halving it and move towards scrapping it, and that remains our position.

"We want to see APD go because we think that is in the best interests of growing traffic at our airports."