The buildup to the Paris Olympics entered its final year on Wednesday as International Olympic Committee president Thomas Bach hailed the "very, very good" preparations.

Having sailed down the River Seine on Tuesday to get a taste of the spectacular opening ceremony on July 26, 2024, Bach formally invited 203 countries to take part in the Summer Games.

Russia and Belarus, its ally in the invasion of Ukraine, are not among the countries invited.

The IOC has however left the door open for Russian and Belarusian athletes to take part as neutrals in Paris without their teams competing.

The participation of Russians and Belarusians could trigger a boycott by Ukraine.

Bach refused to be drawn on when the IOC would make a decision on the issue, but noted that many sports federations had heeded his body's call to allow Russians and Belarusians to take part as neutrals in qualifying events.

"It will depend on the further developments," the German told reporters. "We see now international federations applying our conditions for the participation of neutral and individual athletes.

"We will supervise this... based on the result of this we will at the appropriate time take a decision."

- Potential Ukrainian boycott -

He said, however, a decision would not be taken at the IOC Session in the Indian city of Mumbai in October.

The potential difficulties were underlined at the world fencing championships on Wednesday when Ukraine's Igor Reizlin withdrew from his epee bout with Vadim Anokhin in line with his government's policy of barring athletes from competing against Russians.

Ukraine's sports minister Vadym Gutzeit was ambivalent about a boycott of the Olympics themselves when he spoke to French newspaper Le Monde on Tuesday.

"We have yet to take a decision concerning the Olympic Games," he said.

"We are awaiting a final decision and to know if (the Russians and Belarusians) will be authorised to compete or not."

- Sponsorship boost -

The French organisers were boosted this week when luxury brand LVMH announced it will be a "premium partner" of the Paris Olympics, bringing sponsorship close to the target of 1.24 billion euros ($1.37 billion).

"We still need a few tens of millions of euros to reach the budget we set, but it's clearly a very good thing, even if we were confident," a senior member of the organising committee said.

Organisers will pray there is no repeat next summer of the riots that erupted in the Parisian suburbs and around France earlier this month after a policeman shot dead a 17-year-old youth at a traffic stop.

Tony Estanguet, the head of the Paris 2024 organising committee, told AFP this week he did not have any "big concerns" with 12 months to go.

"I am very satisfied by the way the project is advancing. Yes there are issues every day that need resolving, but that's why the Games are in 2024 and not 2023."

The tone will be set by the opening ceremony on the Seine, the first time in the history of the Summer Olympics that it will take place outside a stadium.

But the prospect of securing a six-kilometre stretch of the river with up to half a million spectators is giving the security forces a headache.

"Clearly, it is not something we have ever done," a top official said, speaking on condition of anonymity. 

"Securing nearly six kilometres of route with so many people present is a real challenge."

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