The buildup to the Paris Olympics entered its final year on Wednesday as International Olympic Committee president Thomas Bach said the preparations were well on track.

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.

The list does not include Russia and Belarus, and its ally in the invasion of Ukraine, the IOC has however left the door open for Russian and Belarusian athletes to take part as neutrals in Paris without their teams competing.

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." Bach said.