That was the stark warning from new analysis by the World Travel and Tourism Council (WTTC), issued on Monday (February 4).

The WTTC says no deal puts 300,000 travel and tourism jobs in the UK at risk, and 400,000 across the wider EU.

This would come at a cost, it estimates, of £18.6 billion to the UK economy, and a further £22 billion to the 27 remaining EU economies.

According to the WTTC, travel and tourism contributes about €1.5 trillion to the EU’s GDP (10.3%) and supports 27.3 million jobs (11.7%).

The UK sector is worth £213.8 billion (10.5% of GDP) and supports about four million jobs (11.6%).

The WTTC’s analysis is based on the International Monetary Fund’s forecasted 7.7% fall in economic activity across the UK resulting from a no-deal Brexit.

Gloria Guevara, WTTC president and chief executive, said: “The UK is the fifth largest travel and tourism economy in the world. Given its importance of the UK economy, it is now clear a no-deal Brexit would have a dramatic impact on one the UK’s most important economic sectors.

“If the IMF prediction on the wider economy is realised, there would be a total cost across Europe of more than £40 billion and more than 700,000 jobs compared to our projections. Our members are already seeing an impact on their businesses and workforce.”

The WTTC has identified four factors the UK must strive to achieve during its Brexit negotiations to minimise the impact.

These are: continued access to the single aviation market; visa-free travel between the UK and EU; mobility of labour for travel and tourism employees; and security cooperation to avoid hard border checks.