London, July 10 : Seven-time Grand Slam doubles winner Jamie Murray became the latest player to express doubts about travelling to the United States for the US Open that starts on August 31. Murray said that the US seems to have regressed in the battle against coronavirus and the increased number of cases in the country means that he would be more comfortable staying back. "It seems they have regressed in the States and there are a lot more cases coming up again," Murray is quoted as saying by The Guardian. "Certainly other states have been struggling. The curve has been going back up. In New York they are talking quarantines for people from certain states. As a player, you want stability. We don't have that. You cannot even book a flight to New York just now. "In Europe, as far as I am aware, it seems like they are a lot further along with the virus than America. In France they are talking about 40-60% fan capacity, which won't be the case in America. I'd imagine the conditions will be a lot easier or maybe less stringent, more under control than in the States. That's what is annoying." While Murray's younger brother and former World No.1 Andy has said that he will be participating at the US Open, the likes of Rafael Nadal and World No.1 Novak Djokovic have all expressed their doubts on participating in the Grand Slam. "I'd imagine it would be very difficult for the ATP to support the US Open going ahead if the draw has to quarantine coming back to Europe," said Murray. "I am sure there will be some interesting conversations to be had in the next few weeks. "A lot will depend on what you can do once you finish the tournament in terms of getting to Europe. If I have the option of playing one Masters series and one Grand Slam [the US] -- or two Masters series [Madrid and Rome] and one Grand Slam [the French Open] because of quarantines -- then I will choose two Masters series and one Grand Slam. You cannot do both." /IANS