French President Emmanuel Macron has promised to swim in the River Seine which is being cleaned up for the Paris Olympics as he toured a new complex that will house athletes.

Mr Macron cited pollution reduction in the Seine as one of the Games’ positive long-term impacts.

He noted “extraordinary” public-funded investments being poured into making the river — largely off limits to bathers since 1923 — swimmable again.

Asked by a journalist whether he would bathe in it, Mr Macron replied, “Me, yes, I’ll go.”

OLY Paris Games Olympic Village Inauguration
France’s President Emmanuel Macron is shown the Olympic village (Ludovic Marin, Pool via AP)

However, he refrained from saying when.

“I’m not going to give you the date – there’s a risk you’ll be there,” he said.

Regardless of whether he does indeed don trunks, Mr Macron’s visit to the high-security Olympic village served to highlight how the Paris Games are helping to transform some disadvantaged neighbourhoods in the French capital’s poorer suburbs.

The eco-friendly village led to nearly 2,000 jobs being created, with 1,136 going to local residents.

It cost about 2 billion euros, most of it investment by property developers but also including 646 million euros (£) from public funds.

The Olympic construction company, Solideo, transferred the village to Paris Games organisers on Thursday, symbolically handing over a large key, with Mr Macron watching.

“It’s a very big day,” he said. “It’s a demonstration that France is a nation of builders.”

In a city repeatedly hit by deadly extremist attacks, security is the biggest challenge for organisers as they ready Paris for the July 26 to August 11 event and the Paralympics from August 28 to September 8.

“Obviously, it’s been an obsession since the beginning.” Mr Macron said. “We have a colossal amount of work being done in advance.”