Ryan Moore has been advised by a specialist to have "complete rest" having been "a bit sore for the last couple of weeks".
Moore has not competitively ridden since Sunday and went on holiday with his family to Portugal soon afterwards.
In a statement, the star jockey said he will only return to the saddle when he is fully fit.
Moore said: "I have been a bit sore for the last couple of weeks and been advised by a specialist that complete rest is the best option.
"I'm not going to rush it as I want to be 100 per cent for all the major races in the autumn so I'm going to play it by ear, but hope to be back soon."
Moore, 32, would have been expected to ride the Aidan O'Brien-trained Caravaggio, ante-post favourite for next year's 2000 Guineas, in the Keeneland Phoenix Stakes at the Curragh on Sunday.
Speaking at Leopardstown on Thursday evening, O'Brien confirmed the mount in the Group One showpiece at the weekend will now go to Seamie Heffernan.
York's big four-day Ebor Festival begins on August 17, where the likes of Minding, whom the jockey has ridden to five Group One victories, could run in the Juddmonte International Stakes and Darley Yorkshire Oaks.
Earlier this week, O'Brien said he had been aware Moore "was having trouble with a hip", adding "I knew that the last while and you could see he was lame while he was walking".
Bookmakers expect defending champion Silvestre de Sousa to take full advantage of Moore's absence and land a second Stobart-sponsored jockeys' championship.
Coral cut the Brazilian to 1-6 from 1-4 favourite, with James Doyle the 4-1 second-favourite. Moore was eased to 8-1.
Spokesman David Stevens said: "With Ryan Moore out of action for the foreseeable future, a title repeat looks to be Silvestre de Sousa's for the taking, with James Doyle now the Brazilian's closest challenger according to the betting."