Sarah Smith
Scotland Editor

The SNP are already preparing for the possibility of another referendum.

They have experts working hard on formulating a new economic case for independence, considering key questions such as what currency an independent Scotland might use and how they would cope with the sharp fall in the price of oil.

Other Yes supporting campaign groups have already started fundraising.

Image source, Getty Images

But calling another referendum would still be a gamble, and the consequences of defeat could be disastrous for Nicola Sturgeon.

To lose two referendums in quick succession could set back the cause of Scottish independence for at least a generation.

And there could be a high personal cost. Both Alex Salmond and David Cameron resigned immediately after losing referendums. There would be an expectation that Nicola Sturgeon would have to do the same.

But still, every time the first minster mentions the possibility of another vote she makes it seem increasingly likely.

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Scottish labour leader Kezia Dugdale also decides to focus on oil and says the OBR confirmed that oil and gas actually cost the Treasury money last year.

At the first opportunity they have come together again, says Mr Swinney while pointing to the Tories and the Labour. 

This receives a raucous response from the SNP backbenches.

Mr Swinney details Scottish government support for the oil and gas industry and the North East of Scotland.

The deputy first minister says today there has been an opinion poll showing support for independence at 50% in Scotland , external .

He says that the people of Scotland are being exposed to the hard right politics of the Conservatives and the mess on Europe.

Ms Davidson asks if there is any economic evidence that Scotland would be better off if it was independent.

The deputy first minister says the Tories are not interested in supporting the oil and gas sector.

Mr Swinney says there are grounds for a great deal of optimism.

Ms Davidson said the Oil and Gas Industry welcomed the Chancellor's measures of support.

She added that most people in Scotland don't want another independence referendum, which is "common sense".

The chancellor has  used his budget  to outline plans to help the North Sea oil and gas industry.

Philip Hammond will investigate the use of tax incentives to make it easier for operators to sell oil and gas fields, helping to keep them productive for longer.

A panel of experts will be set up to examine the issue.

A discussion paper on how to help the industry will also be published, Mr Hammond told the Commons.

The Treasury said the moves would further help a vital industry that meets around 50% of the UK's primary energy needs.

• Budget measures 'worth £350m' to Scotland

Ms Davidson says the entire economic prospectus the SNP based the independence argument is "bogus".

Mr Swinney says oil has been a huge bonus for the UK over 40 years.

The deputy first minister adds that the former prime minister said there would be a £200m oil bonus if Scots voted no,he promised a carbon capture project in Peterhead and promised staying in the EU.

He says: "The No campaign was shattered by these broken promises."

Image source, Getty Images

The economic case for independence should not include North Sea oil revenues , the chairman of the  SNP's growth commission, external  has said.

The commission, headed by former MSP Andrew Wilson, was set up by the SNP to help shape its future economic policy.

Mr Wilson suggested that making North Sea revenues central to the economic arguments for independence ahead of the 2014 referendum had been a mistake.

He said any future campaign would need to balance optimism and realism.

Scottish Conservative leader Ruth Davidson asks whether in the 2014 independence referendum did the Scottish government consider oil as a bonus or as the basis of independence

Deputy First Minister John Swinney says oil is a bonus, bringing £300m revenues for the UK and it has propped up the UK economy for many years.

Image source, PA

Deputy First Minister John Swinney will stand in for Nicola Sturgeon in first minister's questions this lunchtime.

The first minister is attending the unveiling of a memorial dedicated to those who served in Afghanistan and both Iraq wars , by Queen in central London today. 

Image source, Paul Day

The sculpture by Paul Day also marks the contribution made by civilians in the conflicts. It is formed of two stone monoliths and a bronze medallion.

Its unveiling in Victoria Embankment Gardens will follow a service for 2,500 veterans on Horse Guards Parade.

More than 800 UK military personnel and civilians died in the three wars.

• Forty-seven members of the armed forces died in Iraq in the 1990-91 conflict
• 179 were killed in the second Iraq war from 2003-09
• and 456 died in Afghanistan between 2001-14
• In addition, 43 UK civilians were killed in the second Iraq war
• and 101 in Afghanistan

Tory MSP Douglas Ross asks what assessment the government has made of ambulance provision in the Moray area.

Health Secretary Shona Robison says the service has been facing increasing challenges.

Ms Robison says the review has been undertaken to ensure the service is safe and to shape its future provision.

Image source, bbc

Ms Baillie Says there has been no GP's available at weekends in the Vale of Leven and asks if there will be further cuts.

Ms Robison says the Vale of Leven service was closed due to staff shortages and transport was provided to an alternative service.

The health secretary says the review should be allowed to take place before any decisions are made.

Labour MSP Jackie Baillie asks what the government's position is on NHS Greater Glasgow and Clyde’s review of GP out-of-hours services.

Image source, bbc

Transport Minister Humza Yousaf says the Bill is currently subject to parliamentary scrutiny.

Mr Kerr says stakeholders says the merger is unnecessary and that there are safety concerns.

"What is the Scottish government trying to fix?" He asks.

Mr Yousaf says this came about as a result of the Smith Commission and the government are making sure that the BTP has the same accountability as Police Scotland. 

He says the way Mr Kerr has characterised opinion from the rail industry is incorrect and invites the Scottish Conservatives to contribute to the consultation. 

Image source, bbc

The chief constable of British Transport Police has warned plans for a merger with Police Scotland could lead to a loss of specialist skills .

Paul Crowther told Holyrood's justice committee of a "real challenge" in replacing officers amid a "significant outflow of expertise".

He told MSPs of the bomb threats, fatalities and near-death incidents officers often have to deal with.

Police Scotland has called the merger plan  "complex but not insurmountable" .

Holyrood is currently  considering a bill  which would pave the way to absorbing the functions of the British Transport Police (BTP) into Police Scotland north of the border by April 2019.

The Scottish government has  long wanted to integrate the service  into Police Scotland, seeing it as the most "efficient and effective" way of delivering policing across the country.

The  Railway Policing (Scotland) Bill, external  confers extra policing powers on the Scottish Police Authority and the Police Service of Scotland, but further legislation would be needed at Holyrood and Westminster to transfer staff, properties and cross-border policing functions.

Tory MSP Liam Kerr asks whether the government will provide an update on the proposed integration of the British Transport Police in Scotland into Police Scotland.

Image source, bbc

Rural Economy Secretary Fergus Ewing says aquaculture in Scotland provides world class products.

Mr Ewing says there must be appropriate measures in place to ensure minimal impact to Scotland's waters.

Ms Beamish asks if the government will consider measures for "cleaner fish" which is a more environmentally friendly process, she says. 

Mr Ewing says the member raises reasonable points and measures must be in place.

He says there is forthcoming consultations on this. 

Image source, bbc

A  "roadmap" was launched, last October, in a bid to double the size of Scotland's aquaculture sector within 15 years.

Businesses and organisations involved in the sector are seeking to boost the value of Scottish aquaculture from £1.8bn this year to £3.6bn by 2030.

They estimate this will generate more than 9,000 new jobs for the industry.

A working group has launched a new growth strategy, which identifies key actions that are required to achieve the goals.

The group includes representatives of the Scottish Salmon Producers Organisation, Scottish Aquaculture Innovation Centre, Scotland Food and Drink, Association of Scottish Shellfish Growers and businesses in the sector.

Labour MSP Claudia Beamish asks what action the government is taking to address environmental concerns regarding aquaculture industry production targets.