Theresa May is telling the most powerful people in the world right now about her Brexit plan

Lianna Brinded/Business Insider

Theresa May in Davos, Switzerland.

DAVOS, Switzerland - Prime Minister Theresa May is telling the delegates at the World Economic Forum about her plans for bringing Britain out of the European Union.

The WEF event is packed with thousands of the most powerful people in the world - from the CEOs of the largest companies, to the Presidents, Prime Ministers, other political leaders from countries across the globe.

It is the first time since her speech on Tuesday, where she will address the people who will have a hand in shaping a post-Brexit Britain.

She said, "we are all united in our belief that [the new] world is built on the foundations of free trade and globalisation."

"[We will] forge a new place in the world. The road may be uncertain at times but those [who voted for Brexit] believe in a brighter future for Britain and [that's why] we are on a bold ambitious course. They chose a truly global Britain."

This week she confirmed that Britain plans to leave the Single Market as part of its withdrawal from the EU. She also said she would terminate Britain's membership of the free-trade area to have full control over immigration from the European Union.

This is known as a "hard Brexit." A "hard Brexit" is shorthand for Britain leaving the European Union without access to the Single Market in exchange for having full control over immigration into the country.

While company leaders, such as the global chairman of "Big Four" consultancy firm Deloitte David Cruikshank, outlined that May delivering an actual plan on Tuesday is positive and kills off some of the uncertainty that had put them on tenterhooks, companies, as well as political leaders have warned that it could severely harm the UK.

The loss of passporting rights following Brexit is one of the biggest fears in the City of London.

If the passport is taken away, then London could cease to be the most important financial centre in Europe, costing the UK thousands of jobs and billions in revenues. Around 5,500 firms registered in the UK rely on the European Union's passporting rights for the financial services sector, and they turn over about £9 billion in revenue.

Earlier on Thursday, Mayor of London Sadiq Khan said he is telling business and political leaders that "hard Brexit" is terrible for the European Union as well as Britain because if businesses relocate, it will be to Asian countries or the US, not other European cities.

Meanwhile, some of the world's biggest banks are debating on relocating out of London.

Goldman Sachs is considering cutting its staffing numbers in London by up to 50% due to Brexit fears. JP Morgan CEO Jamie Dimon also said that more jobs than previously expected may have to be moved out of the UK as a result of Britain leaving the EU.

And HSBC CEO Stuart Gulliver said that Brexit will push bankers making 20% of London revenue to Europe.