Baroness Tanni Grey-Thompson says athletes need to know now if the 2020 Olympics are to be postponed.
As it stands, the Olympics are due to take place in Tokyo in July but many qualifying events have been postponed.
The Paralympic great says the coronavirus pandemic means there are more important things than sport to consider but has urged for clarity.
"The athletes need to know now and have a better idea of the date it's going to be postponed to," said Grey-Thompson.
"This has a massive economic impact on Japan as well so it's not great at the moment.
"But in the world out there, there's still some really serious stuff going on and it feels a bit frivolous talking about some of this stuff."
The Jurgen Klopp camp
World Athletics chief Lord Coe has argued it is "too early" to make a decision on the Tokyo Games, which are due to start on 24 July.
The International Olympic Committee has said the Games could still begin on schedule despite the coronavirus pandemic causing other events to be cancelled.
Grey-Thompson told BBC Radio Wales Breakfast: "I totally understand why the IOC are trying to hold firm and say they will start at the end of July, but actually it's incredibly difficult.
"A lot of the Athletes' Commission members have spoken out and said it's irresponsible, they're not thinking about the athletes' health.
"I'm sort of in the Jurgen Klopp camp with this. At the moment there's more important things than sport. Sport is important but, you know, this is a worldwide pandemic, and actually the reality of it is all of the final qualification events have just about been called off.
"It's everything else that's affected, not just the Games. It's actually just athletes trying to qualify to get to the Games is really difficult at the moment.
"A decision needs to be (made) really soon because if they're closing down the world ranking lists, it means that you might have a different set of athletes who qualify for the Games than the ones you'd expect.
"You've got athletes who this might be their only chance of making the Olympics. So there'll be a lot of athletes who'll want the Games to go ahead because this is not just a four-year training programme for them.
"For some of them this is their only chance, it'll be 10 years, 15 years plus [of build-up]. But you know spectators at the moment are probably unlikely to be able to go or want to go even if the Games go ahead. Again that changes it."
The Johnson-Thompson case
Grey-Thompson highlighted the challenges different competitors are facing while preparing for the Games in a variety of countries around the world.
"Some athletes are still able to go ahead and do some training, but it's just going to get more and more limited," she added.
Grey-Thompson also pointed to the case of world heptathlon champion Katarina Johnson-Thompson.
"She came back to the UK because she said in France the gyms were shut, the training facility was shut, there was no physio and (she) had been advised not to go out," Grey-Thompson said.
"I think actually athletes have to be quite creative in terms of what they do and the ones that take more charge of their own programme will probably be better able to cope.
"I was trying to put my athlete's hat on and thinking 'if it was me I'd still want the Games to go ahead', but you know at the back of your mind this is really serious stuff."
She added: "If the Games are postponed a month or two months, you can change your training programme; you absolutely can. It's the ability to train at the moment that's quite difficult.
"And if athletes have been at training camps abroad, they'll be coming back, they'll be in self-isolation. That just changes things."