JPMorgan chief Jamie Dimon has said that the financial sector needs to be prepared for a so-called “hard Brexit” scenario and has raised the possibility of moving some jobs from the City of London to other European cities.

Dimon wants the bank to prepare for the worst-case scenario in the negotiations between the U.K. and the European Union, which would prohibit financial firms in London to work with EU-based customers. He said that JPMorgan will probably boost its Frankfurt-based office, given that it already has licenses to operate there but its staff could be moved to Paris, the Netherlands or even Madrid, Reuters reported.

His comments – at the Europlace finance conference in Paris on Tuesday – come at a time when both financiers and European cities prepare for the U.K.’s departure from the EU. In France, the new government is stepping up its efforts to attract bankers and financial institutions from London to Paris.

From tax incentives and new transport connections, French businessmen see a “unique momentum” offering many opportunities and have spoken of the benefits that their home nation offers.

“France’s image will change, we have a young president, I’d say a connected president, a modern president, pro-business, pro-Europe,” Gerard Mestrallet, chairman of the utility firm Engie, told CNBC on Tuesday at the sidelines of the conference.

“We are living a unique momentum for the Paris financial market place,” he added.

France’s Prime Minister Edouard Philippe is due to address investors and professionals from all fields in the financial sector at the conference in Paris later on Tuesday. His speech is part of a wider initiative that the new executive is carrying to make France more business friendly.

Philippe has promised a substantial tax break of up to 50 percent for financiers, the right to exclude foreign properties and assets from the calculation of wealth tax for eight years and scrapping the highest bracket of payroll tax on bankers. Furthermore, France will also reduce corporate tax to 25 percent and it offers a personal income attack at a lower rate than Germany and the Netherlands.

Such initiatives mark a clear difference from the previous executive, when former President Francois Hollande heavily taxed the wealthiest in French society.

Severin Cabannes, deputy CEO of Societe Generale, told CNBC on Tuesday that France usually has two weaknesses: Tax instability with changes in government and a very rigid labor market. However, President Emmanuel Macron and the cabinet led by Edouard Philippe are addressing both subjects.

He added that “it’s a bit early to say” if the measures will be enough to attract people from the City of London, “but Paris has obvious strengths on (the) continental Europe market, clearly,” he said.

“Paris is the first place for equity exchanges, first place for (the) asset management industry and Paris is the first (place) in intercontinental Europe for the banking industry,” he mentioned.

At the moment, only HSBC has said it will move 1,000 jobs from the City of London to Paris. However, other kinds of financial firms are assessing whether Paris could be a good alternative to London, including the world’s largest asset management firm BlackRock.

Christophe Charlier, chairman at Renaissance Capital, told CNBC that Paris Tuesday can be a “credible” alternative.

“Given France’s cultural ties and economic ties around the emerging markets and the presence of major international French banks already in London and internationally and large pension funds like Amundi, I think France and Paris have a great chance of becoming even more of an international market than it already is,” he said.

Financial institutions based in the U.K. have to submit their post-Brexit plans to the Bank of England by July 14, even though the U.K. government has just barely started exit negotiations with the European Union.

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