The assessment was made by Sergei Eliseev, President of the All-Russian Sambo Federation and the European Sambo Federation, Russia’s official state news agency TASS reports.

"The results will be unpredictable due to the change in weight categories, since the leaders have not yet decided. I think it will take a long time for stabilisation here," Eliseev said.

Eliseev maintained that the changes to the rules were "minor", adding: "In particular it concerns weight categories and ages.

"Weight categories have been reduced to seven, and for juniors to eight."

During three competition days, athletes will compete for sets of medals in 22 new weight categories.

For the men the categories will be under-53 kilograms, 58 kg, 64 kg, 71 kg, 79 kg, 88 kg, 98 kg, over 98 kg.

For the women, they will be under-50 kg, 54 kg, 59 kg, 65 kg, 72 kg, 80 kg, over 80 kg.

The combat sambo categories will be under-58 kg, 64 kg, 71 kg, 79 kg, 88 kg, 98 kg, over 98 kg.

The winners of the tournament will earn the right to participate in the World Championship, which is due to be held from November 16 to 18 in Moscow.

Silver medallists will be eligible for the European Championship, scheduled for May 21 to 22 in Italy.

The decision to reduce the weight categories in sambo was made on October 1 2019 at a meeting of the executive committee of the International Sambo Federation (FIAS).

Sambo received provisional recognition from the IOC in November 2018.

Earlier this week the FIAS President Vasily Shestakov said he was hopeful that full Olympic recognition for the sport would be considered by the IOC later this year.