WESTMINSTER'S attempted power grab could expand and "evolve" without consent, the UK’s constitution minster has admitted.

Cabinet Office minister Chloe Smith told MSPs that there was nothing in the Brexit Bill to stop the list of 24 devolved powers that London is seeking to take control of after Brexit from expanding.

Under the current version of the EU Withdrawal Bill, most of the 111 powers in devolved areas would come back to Holyrood, with 24 currently marked to stay with Westminster for the foreseeable future.

The UK Government has claimed that the powers would be devolved back to the Scottish Parliament following the creation of UK-wide common frameworks.

While Nicola Sturgeon has stated that these frameworks must be established with consesnt, the UK Government claim that would give the Scottish Government a veto on which powers they could or could not retain.

SNP Westminster leader Ian Blackford said on Wednesday that he did not expect agreement.

At Holyrood's constitution committee, Scottish Secretary David Mundell stated that the list of powers that Westminster should hold on to is not set in stone.

He repeatedly refused to rule out that the UK Government could impose the Brexit Bill on Scotland against its will.

SNP MSP Ivan McKee asked Chloe Smith if there was anything that could prevent Westminster from adding to the list of 24 devolved powers that would be retained.

She initially refused to answer before admitting: “That agreed list can evolve. I would actually characterise that as a positive thing.”

When McKee went on to suggest that Westminster could then expand its power grab as it saw fit, she responded that the Scottish Government could also choose to do so.

She went on to clarify that this would mean adding powers to the list, but not taking any powers off the list.

Mundell went on to say that it would not be helpful for the list of retained powers to be definitive, and instead prefers an option that provides more "flexibility".

The committee’s SNP convener, Bruce Crawford, enquired whether there was a chance that the UK government would add to the list without the consent of Holyrood.

Mundell said that that would "not normally" be the case, but refused to rule it out completely.

He concluded: “The agreement is predicated on ‘not normally’, so we wouldn’t normally add to the list without the agreement of the Scottish Government and Welsh Government.”