ABORTION, human fertility and the withdrawal of medical treatment from the dying could be among new powers devolved to Holyrood in the event of a No vote, the Scotland Office has suggested.

With the referendum approaching, the Scotland Office has said whether to devolve the highly sensitive issues is a "live" question and they could feature in high-level talks on more powers if Scots choose to keep the Union.

The comments were made following a Freedom of Information request by the Sunday Herald.

Although the NHS is devolved to Holyrood, many ethically sensitive issues remain reserved to Westminster, including abortion, human fertility and embryology, surrogacy and the transplanting of living cells and organs between species.

Tony Blair's Labour government refused to devolve the issues when it created the Scottish Parliament in the late 1990s, while the Calman Commission of 2009 said there was an "absence of compelling evidence" for devolving them.

In April last year, the Sunday Herald requested access to a secret Government archive on the debate inside Blair's government on the subject.

It is understood the files show then Scottish Secretary Donald Dewar arguing for devolution of the issues, but Blair and others opposed.

After the Scotland Office refused to open the file, the Sunday Herald appealed unsuccessfully to the Information Commissioner's Office (ICO).

In its decision last week, the ICO said there were strong public interest arguments in favour of releasing the material, which it described as "frank, candid and detailed".

However, the ICO ruled the wider public interest favoured keeping the file secret, as disclosure posed a "very real risk of a chilling effect on future policymaking in this area".

The ruling revealed the Scotland Office had used the referendum to argue for continued secrecy.

"The Scotland Office argued that key to its basis for [non-disclosure] was the fact that the wider question of what powers should be devolved to a Scottish Parliament remained a 'live' question," the ICO reported.

"The Scotland Office noted that all of the UK parties ... are actively considering what further powers could be devolved to the Scottish Parliament in the event of a No vote.

"The Scotland Office suggested it was possible the matters covered by the withheld information could form part of these discussions."

The ICO said it accepted that, if the referendum produced a No vote, "in light of the commitment by the UK political parties to review the nature of the devolved powers, this policy may well become live once again".

First Minister Alex Salmond has previously said he favours cutting the time limit for terminations from 24 to 20 weeks. Health Secretary Alex Neil also favours lowering the limit north of the Border.

However, Deputy First Minister Nicola Sturgeon is against lowering the limit below 24 weeks.

In 2012, she said it would risk "sending abortions back to the back streets and making them less safe for women".

A spokesman for the Catholic Church in Scotland said: "There are concerns about legislation at the European level from the moral and ethical perspective, at Westminster and at Holyrood.

"The Church in Scotland is primarily concerned with the composition of the legislation rather than the venue for it.

"We always seek to remind policy makers and law-makers of the dignity and sanctity of human life when they legislate in these areas."

An SNP spokesman said: "The Scotland Office is once again holding information back. The question would have to be why, as the reason given is very unclear."

A Scotland Office spokesman said: "The issue of whether the law relating to abortion and other sensitive medical areas should be devolved was considered in 1997. It was discussed by the Calman Commission in 2009.

"It remains possible that it may be considered again when further devolution is taken forward in the event of a 'No' vote in the referendum."