The Scottish Government’s emergency Brexit legislation has passed its second stage at Holyrood after 11 hours of scrutiny.

MSPs forced through changes to the Continuity Bill as they accused ministers at Holyrood of attempting their own “power grab”.

The UK Withdrawal from the European Union (Legal Continuity) (Scotland) Bill has been brought forward amid an ongoing row with Westminster over the return of devolved powers from Brussels once Britain leaves the EU.

The @SP_FinCon has just completed its second day of Committee for the #ContinuityBill. 231 amendments were considered over the course of the two sessions. Members and Clerks alike look like they've just gone 12 rounds with Lennox Lewis. — Matt Hamill (@Mattph82) March 14, 2018

The Scottish and Welsh Governments have refused to recommend granting legislative consent to the UK Government’s EU Withdrawal Bill, which will transpose EU law into UK law following Brexit, branding it a Westminster “power grab”.

The Scottish Government claims the Continuity Bill is a necessary backstop to safeguard devolution and ensure legal continuity if no agreement is reached in negotiations over the UK Withdrawal Bill.

No agreement was struck on the UK legislation on Wednesday following talks and First Minister Nicola Sturgeon said the areas of disagreement are “not insignificant but neither are they insurmountable”.

But in a marathon scrutiny session by Holyrood’s Finance and Constitution Committee, opposition MSPs raised concerns that measures in the Scottish continuity legislation are a bid to seize powers for Holyrood ministers.

Brexit Minister Mike Russell offered concessions on the controversial issue of giving Scottish ministers the power to keep pace with European Union regulations post Brexit.

The legislation had originally proposed these last up to 15 years – an initial five years and two possible extensions of the same length.

However, the committee voted to reduce this to a maximum total of five years – an initial three years after Brexit with two one-year extensions then permissible.

This change to Section 13 of the legislation was supported by Conservative, Labour, Green and Liberal Democrat MSPs.

Liberal Democrat MSP Tavish Scott said Section 13 “can only really be described as a ministerial seizure of the most extensive powers”.

At #ContinuityBill committee, @tavishscott says Section 13 is a power grab for 15 years and proposes to remove it from the Bill and for ministers to bring it back separately if they want later — Scottish Lib Dems (@scotlibdems) March 14, 2018

He warned if this Bill was not changed it would mean for 15 years “ministers of any persuasion can create new laws, abolish old laws, create new quangos”, and could even “imprison people for up to two years under offences brought to the statute book by regulations and not primary legislation”.

His concerns were echoed by Labour’s James Kelly who claimed Section 13 was Brexit Minister Mr Russell “using the legislation to enhance the powers of Scottish ministers”.

Mr Russell said if Scottish ministers could not make law to keep up to changing European regulations, there risked being “serious damage” to industries such as the fish farming sector.

He added: “We have to balance the requirement for scrutiny, ministerial restraint, ministerial supervision, with the requirement to do something in these exceptional circumstances.”

MSPs on the committee spent 11 hours scrutinising the 231 amendments in detail, leading to the highly unusual situation of the Parliament sitting to 10.35pm on Tuesday for four hours and 50 minutes of debate.

Consideration was resumed at 8am on Wednesday for three hours and 50 minutes, before resuming at 6.30pm and finally finishing at 8.50pm.

Mr Russell said: “I welcome the engagement and scrutiny we have seen from across the chamber over the last few days, which shows the Scottish Parliament working effectively.

“We have received a number of suggestions during this process which we recognise will help to improve and strengthen the bill.

“The Scottish Government continues to talk with the UK Government to find agreement on the EU Withdrawal Bill, but as drafted we could not recommend consent to that bill as it undermines devolution and allows the UK Government to unilaterally take control of devolved powers.

“In order to both protect devolution and prepare Scotland’s laws for Brexit we need to proceed with our own Continuity Bill and I look forward to further engagement with parties across the Parliament as we move this process forward.”