Players should not be penalised because of the "decisions of an authoritarian leadership", the head of the Women's Tennis Association says.
Steve Simon says he "feels very very strongly" that players from Russia and Belarus should be able to continue to compete on tour.
They are not currently allowed to play under their country's name or flag, or play in any team competitions.
"You never know what the future may bring," Simon told BBC Sport.
"But I can tell you that we have never banned athletes from participating on our tour as the result of political positions their leadership may take.
"So it would take something very, very significant for that to change, but again we don't know where this is going."
The WTA and ATP Boards suspended the combined event scheduled for Moscow in October following Russia's invasion of Ukraine. And all International Tennis Federation tournaments in Russia and Belarus have been cancelled indefinitely.
But none of the international governing bodies are currently minded to follow sports such as athletics, badminton, canoeing and rowing in banning individual Russian and Belarusian athletes from competing.
However, if national governments start to prevent these players entering their country, the tours will have no say in the matter.
"It will force us to change our position, because obviously we have to follow the rules of government," Simon continued.
"I feel very, very strongly that again these individual athletes should not be the ones that are being penalised by the decisions of an authoritarian leadership that is obviously doing terrible, reprehensible things.
"But if that happens, which is again part of the overall strategy of making Russia, and Russian citizens, pay the consequence for the decision their government has made, then it won't be something that we support.
"We are hopeful that they will refrain from that because I think there are an awful lot of other issues that go with it.
"I don't think you can just pick on the athletes. What are you going to do with the [Russian] refugees that come in? Are you going to treat the refugees differently than the athletes?
"I'm hoping that we continue with the sanctions, we continue doing everything we can to get peace, but again these people are the innocent victims of that, and being isolated as a result of these decisions I don't think it's fair."
The UK Sports Minister Nigel Huddleston said on Tuesday that Russian players might need to make clear they are not supporters of Vladimir Putin to be allowed to compete at Wimbledon this year.
"Absolutely nobody flying the flag for Russia should be allowed or enabled," he said at a hearing of the Digital, Culture, Media and Sport Committee.
"We need some potential assurance that they are not supporters of Putin and we are considering what requirements we may need to try to get some assurances along those lines," he added.
The All England Club is actively involved in those discussions.
Peng Shuai: 'No significant progress has been reached'
Simon also said there will be a decision "very, very soon" on whether to cancel all of this year's WTA tournaments in China.
Events in China and Hong Kong were suspended after Peng Shuai accused the former Chinese Vice-Premier Zhang Gaoli of sexual assault. Peng has since denied that she made the allegations.
The WTA wants the Chinese authorities to hold a "full, fair and transparent" investigation before any of the tournaments can go ahead.
"A lot of work continues to go on," Simon said.
"We will never stop working on the process. We are strong and we will be resilient. What we have said we were going to do so far, we are not going to waver from that. But no significant progress has been reached."
Simon has not been able to have a private conversation with the former doubles world number one since she made the accusation. A decision to cancel the sequence of tournaments planned for China, which are set to begin in late September, could be taken when the WTA Board meets in Miami later this month.
Nine tournaments were staged in China in 2019, and Simon says cities in Europe, the Americas and Australia have expressed an interest in filling the void.
The financial repercussions of withdrawing from China altogether are huge, but the WTA has at least recently ended its long search for a global title sponsor.
The medical technology company Hologic has agreed the "largest global sponsorship in WTA history".
"They became aware of us because of the stance we took on Peng Shuai," Simon added.
"I think it encouraged them that we were someone that they want to talk to."