Ukrainian athletes, Bach said on the sidelines of the World Ski Championships, "know how much we share their grief, their human suffering and all the effort we're taking to help them" in the wake of Russia's invasion of their country almost 12 months ago.
Bach added: "It is not up to governments to decide who can take part in which sports competitions because this would be the end of international sport competitions and of world championships and Olympic Games as we know it."
Ukrainian President Volodymyr Zelensky, who has called for a boycott of the 2024 Paris Olympics if Russian athletes are allowed to take part, said Friday their presence would be a "manifestation of violence".
Ukraine has reacted furiously to the International Olympic Committee's announcement last month that it was exploring a "pathway" to allow Russian and Belarusian competitors to take part in the Paris Games, under a neutral flag.
Kyiv fears Russia's President Vladimir Putin, whose forces will soon move into a second year of their invasion of Ukraine, will seek to gain political advantage from the participation of Russians at the Olympics next year.
IOC president Bach has described Ukraine's calls for a boycott of the Games as contrary to the "principles we stand for".
"Our mission is a peace mission," Bach said Sunday.
"History will show who is doing more for peace, the ones who try to keep lines open and communicate or the ones who want to isolate and divide... our role is bringing people together.
"We're trying to find a solution that is giving justice to the mission of sport, which is to unify not to contribute to more confrontation and more escalation."
Bach added: "With every Ukrainian athlete, we can, from a human point of view, understand their reactions, we share their suffering, that's why we're in full solidarity with them, this is why we are supporting them, whether they're in Ukraine or outside.
"We're supporting 3,000 members of the Ukrainian Olympic community to have a strong Ukrainian team in Paris" for the 2024 Olympic Games.
"Every Ukrainian athlete can be rest assured that we are standing in full solidarity with them and all their comments are taken very, very seriously into consideration
"But with regard to participation of athletes we have to accomplish our peace mission and that is a unifying mission of bringing people together."
Bach refused to commit to visiting the Ukrainian frontline in the key city of Bakhmut. He was invited by Zelensky to "see for himself that neutrality does not exist".
"I have seen a tweet, but there are no ongoing discussions," he said, adding that talks on the pathway for Russian and Belarusian athletes' potential participation in Paris 2024 were not yet underway.
"We are talking about the sporting competitions to take place this year. There is no talk about Paris yet, this will come much later," said Bach.
The IOC and the international community, he said, had to address the "serious concerns" of the UN human rights council that an exclusion of Russian and Belarusian athletes "only because of their passports is a violation of their rights".
The second issue, Bach added, was the paradox of certain sports, like tennis, already allowing their participation, albeit under a neutral flag.
"We have seen a Belarusian player under neutral status winning the Australian Open. So why shouldn't it be possible in a swimming pool for instance or in a gymnastics?"
© 2023 AFP