Jeremy Corbyn has accused Theresa May of preparing to launch a "trade war" with Europe if she does not get her way over Brexit.

With speculation mounting that the Prime Minister will announce the UK is to leave the single market, the Labour leader said she was pursuing an "extremely risky" strategy.

He sharply criticised a warning by Chancellor Philip Hammond the Government could retaliate by slashing corporation tax if UK firms faced new tariff barriers outside the EU.

"It seems to me a recipe for some kind of trade war with Europe in the future. That doesn't really seem to me a very sensible way forward," he told BBC1's The Andrew Marr Show.

He said the Prime Minister's negotiating strategy risked damaging British exporters.

"She appears to be heading us in the direction of a bargain basement economy on the shores of Europe where we have low levels of corporate taxation, we will lose access to half our export market," he said.

"It seems to me an extremely risky strategy. There needs to be more discussion, more consultation and recognise that there is a close co-operation with Europe that is going to have to continue when we are outside the EU."

Mr Corbyn confirmed that Labour would not seek to block the Government from triggering Article 50 - marking the start of the formal two-year negotiating period - but indicated it could seek to ally with MPs from other parties in the Commons to influence what shape Brexit takes.

"The Brexit vote isn't a one-off thing. It has got to be agreed by 27 national parliaments, it has got to be agreed by the European Parliament. There is quite a long way to go on this," he said.

"It is going to have to keep coming back to the House of Commons and we will make sure it does keep coming back to the House of Commons. We will keep on pressing the Government on this.

"There are MPs in all parties that must be concerned about the future of industries in their constituencies, must be concerned about the future trade relationships we have."

After Mr Corbyn was criticised for issuing mixed messages on immigration from the EU after Brexit, he said that the UK would still need workers from Europe.

"It is going to be part of the negotiations about access to Europe. If we are going to have access to a single market then there is going to be an issue surrounding that," he said.

"Let's look at the issue of the flow of people in the context of access to a free market. Let's not blame migrants for the problems we have.

"What we are going to be doing is negotiating a trade arrangement with Europe to make sure we are able to access those markets.

"It will involve people from Europe working here just as much as there are two million British people living and working in the European Union. Are we going to cut ourselves off completely? I don't think so."

In contrast, shadow foreign secretary Emily Thornberry said Labour was not going to "die in a ditch" for the sake of the continued free movement of labour and that there would have to be new rules after Brexit.

"We're not going to die in a ditch for the sake of freedom of movement European-style," she told ITV's Peston On Sunday.

"Part of the debate during the referendum was that people's feeling of anxiety about the amount of migration coming into the country and if we're leaving the European Union then we need to make sure that we have fair rules and properly managed migration but it's all subject to negotiation because our economy comes first."