LAUSANNE, Switzerland -- The International Olympic Committee has decided it can pick both Los Angeles and Paris as Olympic host cities in September when the 2024 and 2028 Summer Games rights should be awarded at the same time.

IOC members voted unanimously Tuesday to seek a consensus three-way deal between the two bid cities and the IOC executive board. Talks will open with Paris widely seen as favorite for 2024.

If a deal falls through, only the 2024 hosting rights will be voted on when the IOC next meets Sept. 13 in Lima, Peru.

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Agreement seemed assured by the reaction of the two mayors. Eric Garcetti of LA and Anne Hidalgo of Paris emerged on stage holding hands to acclaim the decision.

2024 candidate city delegation of Paris led by French President Emmanuel Macron gesture during the briefing of 2024 Olympic Games candidate cities Paris and Los Angeles ahead of final election of 2024 Olympic host city, in Lausanne, Switzerland July 11, 2017. Pierre Albouy/Reuters

The mayors were joined by IOC President Thomas Bach who raised an arm of each in a shared gesture of triumph.

A deal to make both cities winners would fulfil a strategy Bach set in motion last December to help safeguard a stable future for the signature Olympic event.

"With Los Angeles and Paris, there are two fantastic cities from countries with a profound Olympic history," Bach said earlier.

The IOC approved the expected double award after hearing both cities present their 2024 hosting plan at a conference center in the Olympic capital city Lausanne.

Both cities used 45 minutes of videos and speeches, including French President Emmanuel Macron promoting the Paris cause, in a closed-door session with International Olympic Committee members to explain how they would host the 2024 Olympics.

Macron said Paris is better suited to defend the games' values of openness and tolerance, which is being challenged by "others."

"Everything which makes this Olympic spirit and which gathers us today and today's values are at risk, and I think it's very consistent with the French DNA, the French mission," Macron said.

Earlier Tuesday, the mayors of Los Angeles and Paris said they could work toward a deal.

"We look forward to working together maybe not in competition but collaboration with Paris," LA Mayor Eric Garcetti said at a news conference after his city's bid officials opened the campaign event.

French President Emmanuel Macron, Paris mayor Anne Hidalgo and French slalom canoeist Tony Estanguet attend the briefing of 2024 Olympic Games candidate cities in Lausanne, Switzerland July 11, 2017. Pierre Albouy/Reuters

Garcetti and Paris Mayor Anne Hidalgo have long touted their good relations on other issues such as climate change.

"We are all at the disposition and by the side of the IOC which was right to ask itself this question," Hidalgo said at the Paris news conference, citing her friendship with Garcetti as potentially a "key element" to reaching an agreement.

The dual award can give the IOC a decade of stability with two world-class cities touting financially secure bids. LA plans to use only existing venues with zero risk of white elephant venues. This follows years of overspending by Olympic hosts and political defeats to sink potential candidates.

The win-win option also guards against a 2024 loser refusing to bid again for 2028.

It also avoids inflicting a third recent defeat on Paris - which lost with bids for the 2008 and 2012 Olympics - and the United States. New York and Chicago both lost heavily for 2012 and 2016, respectively. Paris also failed with a 1992 bid.

"We lost three times, we don't want to lose a fourth one," Macron said at the news conference. "I'm here to convey the message that there's a strong unity to back this candidacy."

Minutes after Macron spoke, President Trump wrote on Twitter: "Working hard to get the Olympics for the United States [L.A.]. Stay tuned!"