Rafael Nadal has cast doubt over the prospective resumption of the international tennis calendar and insisted he would not currently be prepared to travel to a major tournament due to the coronavirus pandemic.

Global health fears and quarantine restrictions have led to concerns over the practicality of staging the US and French Opens, which are still scheduled to take place in August and September respectively.

And Nadal, who celebrated his 34th birthday on Wednesday, said he would have serious concerns about returning to the tour until the situation has eased enough for players from every nation to be able to compete.

Speaking on a Zoom call with international media, Nadal said: "It's not an ideal situation – if you ask me today if I want to travel to play a tennis tournament, I will say no.

"I am confident they will make the right decisions in the right moment to be sure that if (the US Open) is played it is going to be under extremely safe circumstances – if not, in my opinion, it doesn't make sense.

"We have a worldwide sport and my feeling is that we need to be clear and responsible. It's not the same as football which can be played in one country. When you mix people from every single part of the world the complications are completely different.

"We need to understand that we are suffering an unprecedented situation and my feeling is we need to come back when all the players of all the world are able to travel under safe circumstances.

"If not, in my personal opinion, will we come back? Yes, and I probably will play, yes, but my feeling will be that we are not being 100 per cent fair and correct."

All ATP and WTA events remain suspended until at least July 31, although the six-strong LiveScore Cup, a women's exhibition event in Prague, is taking place this week, and Novak Djokovic has discussed staging a similar event in Serbia.

Nadal, whose quest to add to his current tally of 19 grand slam titles is currently on hold, is playing catch-up having only returned to the tennis court last week following an easing of Spain's strict lockdown regulations.

And it is clear that the Spaniard, who previously suggested he could not see the sport returning in any form in 2020, retains a keen sense of perspective over its short-term prospects.

"I could not practice at my home because I don't have a tennis court – I live in an apartment – so I need to take it step by step," added Nadal.

"I am practising a couple of days a week and I am just trying to give myself the body preparation for what could happen in the next couple of months.

"I can't predict the future. When I said I don't see tennis during the whole season it was because we have been under the terrible circumstances with a lot of people suffering every single day.

"So my mind was not able to think about that. I was thinking about the health of the people and the worldwide pandemic we are still suffering."