How plausible are Johnson and Corbyn's election claims?

Boris Johnson and Jeremy Corbyn have clashed in the first debate of the election, and the first ever British election debate featuring just the prime minister and the leader of the opposition. But how accurate were their assertions?

Claim: Corbyn claimed it would take “at least seven years” to negotiate a trade deal between the UK and the US.

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Reality: The EU took seven years to negotiate and ratify its deal with Canada, not the US. On average it takes 48 months to do a trade deal. It is highly unlikely that a US deal will be struck until the UK agrees a new deal with the EU. The UK only has 11 months to negotiate a deal with the bloc, starting 1 February. The current deadline for a trade deal with the EU is 31 December but many expect the transition period during which negotiations will take place to be extended by one or two years.

Claim: Corbyn said that Johnson told the Democratic Unionist party at its annual conference last year that there would be no border down the Irish sea and now, “well there is”. Johnson says “the contrary” is the case.

Reality: Corbyn is correct. Johnson has struck a deal that will keep an invisible border between Northern Ireland and the Republic of Ireland. This will involve some additional paperwork between Northern Ireland and Great Britain on food and agrifood, which the DUP accepted as the price of a deal. But further goods will also be checked. Exactly which goods and the level of checks could not be decided until the Brexit deal is done when a joint committee of EU and the UK could work out the details.

Claim: Johnson claims voting in a Labour government would mean two referendums next year, one on the EU, one on Scottish independence.

Reality: Labour’s policy is to renegotiate a Brexit deal with the EU and then put it to UK voters in a second referendum within six months. Corbyn did not say which way his party would campaign. Should Labour fail to win a majority next month, it could need the support of minority parties to form a government, including the Scottish National party. Nicola Sturgeon has said she wants an independence referendum before 2021. However, Corbyn has said he would not allow a vote in the “early years” of a Labour government. He also says no deals have been struck with the SNP.

Claim: Johnson claims the Tories are “building 40 new hospitals”.

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Reality: The Conservatives earmarked £3bn earlier this autumn, saying they would build 40 new hospitals. However, it emerged the majority of the funds would go to just six NHS trusts, which each have a major hospital badly in need of rebuilding and have had plans waiting for approval. A further 21 NHS trusts will get £100m seed funding between them for building works on 34 hospitals they need for 2025-2030.

Claim: Johnson said the rate at which Labour would borrow would “push up interest rates for every household in the country”.

Reality: The Conservatives have argued that Labour will spend an additional £1.2tn over five years. However, the Tories did not base their claims on Labour’s manifesto and used estimates that have been disputed as incorrect. The government’s borrowing costs – interest rates – are at historical lows and economists do not expect a dramatic rise soon. Both Labour and the Tories plan to raise public spending back to 1970s levels, according to the Resolution Foundation. The outcome of Brexit will also have an impact on interest rates and the government’s budget deficit – the annual shortfall between income from taxes and government spending. The National Institute of Economic and Social Research estimated Johnson’s Brexit deal would leave the economy £70bn smaller after a decade and would weaken the public finances.

Claim: Johnson said Corbyn would “whack” corporation tax up to “highest in Europe”.

Reality: Corbyn said he would return corporation tax to levels in 2010 when it was 28% which would make it one of the highest, but not the highest in the EU. France’s corporation tax is 31% for companies with an annual turnover below €250m and 33.33% for companies with an annual turnover starting at €250m. Combined corporation tax in Germany is between 30% and 33%.