Wednesday 21 March 2018 14:12, UK
FIFA says the World Cup stadium in the Russian city of Samara requires "a huge amount of work" to be ready on time.
With less than three months remaining before the 45,000-seat venue is due to host a Group A match between Costa Rica and Serbia, the pitch has yet to be laid.
Construction work at the Samara Arena, one of 12 venues that will stage World Cup matches this year, has been hit by a number of setbacks in recent months, putting authorities under additional pressure to deliver a proper venue for the tournament.
"Over the course of this project, we have spoken about delays in Samara," said FIFA chief competitions official Colin Smith.
"Those delays are still evident now even though a lot of progress has been made. There is a huge amount of work to be done."
Smith said the "full support and commitment" of Russian authorities and the venue's contractor were essential for the venue to be commissioned by the end of April as had been originally planned.
"We would expect further progress than this," said Smith. "But what's important to us is that the stadium is commissioned on time, then we have the use of the stadium and we can install all our temporary overlay and equipment that we need for the World Cup."
The stadium will host four group stage matches, including Russia's showdown with Uruguay, a last-16 tie and a quarter-final.
Last August, the venue's contractor said that the work on the Samara Arena was 30 days behind schedule.
Sports Minister Pavel Kolobkov said last year that the authorities were monitoring the troubled stadium's construction and had set up a timetable to track progress and compensate for delays.