Labour leadership contender Owen Smith has pledged to prevent "right-wing Leavers" forcing through an extreme Brexit deal that damages the UK's economy and scientific research if he is elected party leader.

Mr Smith and Jeremy Corbyn, who he is standing against for party leader, were asked a series of questions by the Scientists for Labour campaign group.

Asked about the challenges posed by the prospect of Britain leaving the European Union, Mr Smith it was "extremely damaging to UK science", partly because of the beneficial effects of free movement of people and the single market – both of which some Leave campaigners oppose.

The UK could potentially negotiate a deal in which it leaves the EU but stays part of the single market and maintains free movement.

"As leader I would lead a strong and competent opposition to prevent right-wing Leavers negotiating a right-wing deal," Mr Smith said.

"It is also why I have committed to a second referendum or general election on the terms of Brexit – the people should have the final say on whether they are happy with the Tory deal."

The full questions and answers are below:

Scientists for Labour: What do you see as the main challenges facing UK science and technology as a result of Brexit? What will you do to support this sector across the entire country, rather than just in London and the South East?

Mr Smith: Brexit is extremely damaging to UK science. Free movement and the single market have been positive for UK science. EU programmes such as Horizon 2020, Erasmus and other programmes, and infrastructure funds coming from budget heads like the European Regional Development Fund, are associated with many of our science investments. These are not simply economic considerations but are fundamental to the way in which modern science is undertaken. The government have thus far failed to properly calculate how much that is [let] alone set out a strategy for the future. That is why as Leader I would lead a strong and competent opposition to prevent right-wing Leavers negotiating a right-wing deal. It is also why I have committed to a second referendum or general election on the terms of Brexit – the people should have the final say on whether they are happy with the Tory deal.

However science and technology faces a longer term problem that has carried on throughout successive governments. R&D spending as a percentage of GDP is below the EU average and around half the internationally recognised ambition of 3% of GDP. As part of my £200bn British New Deal, £40bn will be invested in the new industries of the future, and as part of that we will invest £15bn into the Green Investment Bank.

On the second part of your question, I have argued at many meetings during this campaign that we need a strategy that embraces the whole of the UK, partly because of the moral case that demands greater equality across our Nations, but also because it is absurd to disregard the talent pool outside of London and the South East. Countries that have established regional economic policies with mechanisms to engage with scientists and engineers have been able to weather the storm of global economic downturns better than us and we should learn from them. I would want to work with the science community not just in central government but also see them engaged at a regional level to explore how we can maximise the use of the skills we have and to develop the next generation. As an example, we have heard a lot of rhetoric about the Northern Powerhouse but little is happening on the ground. I have pledged that £50bn of the British New Deal will be invested in the North of England.

Successive governments have promised support for evidence-based policy making, but have failed to deliver. How will you ensure that you are well-informed when making policy decisions, given that the current civil service infrastructure does not seem to allow for this?

I sympathise with the question when one looks at the way in which Owen Paterson developed policy based evidence, but there are some good news stories! Since Harold Wilson appointed Solly Zuckerman in 1964 as the very first government chief scientist, there have been steps in the right direction. The network of departmental chief scientists is now well established and the scientific input into policy making is far better than it was. It is at its best when there is a strong science minister (I will come back to that in answer to q6) and a strong GCSA. One of the things I would like to explore with scientists and engineers is whether we can create a better way of drawing in all the expertise that exists. The system for dealing with science advice in emergencies that was radically changed by John Beddington provides a model of what we might consider – not just in emergencies but routinely.

Where would you rank climate change in terms of the current risks to the country, and how would you act to mitigate both its causes and effects? Should nuclear power have a greater role in doing this?

The first duty of a government is to protect its people. Climate change must be treated very seriously and we need to be mindful of our global responsibilities as well as risks to our country. I would start by saying we should be proud of the work Labour did in this area we were last in government. The whole of this debate creates both problems and opportunities for any advanced nation. There is a huge amount of work being undertaken on fuel efficiency, low carbon and zero carbon technologies where the UK has a lot to offer.

The Government is on the path to privatizing the Green Investment Bank, a decision that is wrong for the green economy, and wrong for Britain. Under my leadership, it would be in Government hands. So far the bank has committed £2.7bn to the UK’s green economy generating transactions of £11bn. But to achieve our legally binding environment targets we require an investment of £330bn in the UK’s green economy by 2020 - investment to date is less than half that. So under my leadership, I would capitalise the bank with a massive injection of £15bn over the next five years.

We have increasing power demands which we cannot meet without a mixed portfolio of energy sources, including nuclear. We should be getting on with Hinkley Point, not least because there are thousands and thousands of jobs depending on this project. Prevarication and weakness from the government is jeopardising those jobs.

The NHS currently spends hundreds of millions of pounds funding alternative and homeopathic medicine. Would this policy continue under your Labour government?

I don’t think public money should be used to pay for treatments that aren’t proven to be clinically effective. These matters should be made by clinicians, and based on evidence of what works.

Genetically Modified (GM) crops offer the opportunity to drastically increase global food yields, but have not seen substantial uptake in this country. Would you support their greater use within the UK?

It is hard to envisage feeding a world with 9 or 10 billion people without using novel forms of food production. However I recognise the concerns about genetic modification. In authorising the properly regulated use of any technology, government should proactively address public concerns. I would want to see independent organisations like Sense About Science playing a key role in communicating issues like this in a balanced way.

During the last leadership contest, both the leader and deputy leader promised to have a cabinet-level minster for science. This did not happen. Will you commit to having a cabinet-level shadow minister for science?

The Minister for Science needs to reach well beyond the current role within the department for Business, Energy and Industrial Strategy. There are hugely complex science policy issues that need addressing in almost all departments and in the same way in which the GCSA seeks to bring together science issues by co-ordinating the work of the departmental chief scientists, there is a case for that to happen at a political level. Some recent politicians are acknowledged as being excellent advocates for science without being formal members of the Cabinet. I am open to persuasion as to whether we need to make the post a cabinet appointment, but it is vital that we have a substantial figure in that role who provides the leadership and drive that is necessary.

He was also asked to submitted a short statement setting out his "vision for science and technology" under a Labour Government:

Science is central to the success of any advanced economy as well as being vital to help feed the world and address the challenges of climate change. Britain’s science and technology is world-beating. Think of our history as the birthplace of the Industrial Revolution and workshop of the world. From the steam engine to graphene we have revolutionised the world.

But our world-beating science and technology is under threat. In the short term Brexit poses a profound threat to investment and collaboration. I will lead a strong and competent Opposition to fight against right-wing Brexiteers negotiating a right-wing Brexit deal. It is also why I have committed to a second referendum or general election on the terms of Brexit – the people should have the final say on whether they are happy with the Tory deal.

Over the long term we have failed to invest enough in research and development, and we have allowed our manufacturing strength to wither. Less is invested in research, and fewer people make things. Our economy has hollowed out and we have failed to look to the future. So as part of the £200bn British New Deal, £40bn will be invested in the new industries of the future, and as part of that we will invest £15bn into the Green Investment Bank. I want our country to discover, to invent, to make things, and to sell them abroad. I want us to lead the world again.