COMPANIES operating across the UK could be forced to split their pension funds into separate Scottish and English schemes under post-independence plans being considered by SNP ministers.

First Minister Alex Salmond yesterday confirmed the move was among a number of options being considered to tackle a pensions timebomb that would be triggered by European Union rules in the event of Scotland leaving the UK.

Under an EU pensions directive "cross-border" schemes must be fully-funded. The rule causes potential problems because many British pension schemes are underfunded, with insufficient assets to cover future liabilities.

Other options to address the issue include asking Brussels for an exemption from the directive or requesting a period of grace allowing pension funds to build up their assets.

Speaking at First Minister's Questions, Mr Salmond told MSPs: "We will be looking at the three options."

His chief political spokesman said later no decisions had been taken, but a Government paper setting out a detailed pensions policy for an independent Scotland would be published "soon".

Accountants' body ICAS, which highlighted the problem last week, has warned Brussels is unlikely to give companies the 10-year period of grace many need to bring their funds into line. In the case of UK and Ireland cross-border schemes, Brussels allowed time for them to be split up after the directive came into force.

One leading Scottish actuary, Donald Campbell, of pension consultants Xafinity, has already urged firms to consider dividing their pension funds ahead of next year's referendum.

However, he said splitting pensions would make them more expensive for firms to provide. The Scottish Government also faced pressure to explain how occupational pension holders would be protected, if the country left the UK and separate Scottish schemes were created.

At present 16,000 Scots, whose work pension schemes have collapsed, rely on the UK Government-backed Pensions Protection Fund – which pays most of the money they were due.

Ruth Davidson, the Scottish Conservative leader, said: "The First Minister is clueless on how he would guarantee people's pensions under separation and yet he is willing to gamble the futures of every man, woman and child on his punt to break-up the UK."

Gregg McClymont, Scottish Labour's pensions spokesman, said: "The devil is in the detail on pensions and the fact that the First Minister has not done his homework is glaringly obvious. When it comes to retirement, Scots want certainty and security, not assertion and wishful thinking."

The prospect of major changes to works pensions emerged as Mr Salmond came under fresh attack over his plan for an independent Scotland to enter a currency union with the rest of the UK.

Questioned by Scottish Labour leader Johann Lamont he claimed a sterling zone was in the best interests of Scotland and the UK.

However, he refused to rule out creating a new currency in the event of independence, a plan favoured by many of his allies in the Yes Scotland campaign.

Meanwhile, the Labour First Minister of Wales, Carwyn Jones, entered the currency row, urging Chancellor George Osborne to reject any currency union with an independent Scotland.

He warned it would pose "very real risks" for the rest of the UK and could damage the Welsh economy.

Peter Sinclair, a professor of economics at Birmingham University, said all the currency options open to an independent Scotland were "fraught with difficulty".

He said keeping the pound would result in strict conditions on economic policy that would "make a nonsense of independence". He also warned a separate Scotland would face higher borrowing costs, pushing up national debt by the equivalent of £289 per family per year.

Mr Salmond's spokesman said: "The policy we have set out is a currency union with the rest of the UK. That is the only policy."