Site sources have been in constant contact with the Enquirer warning that the stadium would not be ready for the first planned Premier League game against Liverpool on September 15.
One said: “They have been chucking resources at this for months but it was never going to be ready.
“The roof and cladding are nowhere near finished and some of the components are still being manufactured in Qatar.”
A Spurs statement said: “Recent testing and commissioning has now shown issues with the critical safety systems.
“Urgent follow-up meetings with Mace and the trade contractors are now taking place. We are reviewing the situation and planned timetable to rectify and re-test, after which we shall be in a better position to outline a revised timetable.”
The club was hoping to hold test events on 27 August and 1 September which will now be rescheduled to “take place ahead of any first official match at the new stadium in order to achieve the safety licence.”
The Liverpool game and subsequent match against against Cardiff City on 6 October will now be switched to Wembley, as will the NFL match scheduled for 14 October.
Chairman, Daniel Levy, said: “We know this will be disappointing for all our season tickets holders, premium members and our fans worldwide.
“At the start of the project we asked for your support during what we knew would be a complex and challenging build and now we ask for your continued patience and forbearance.”
Mace has been contacted by the Enquirer for a comment on the delay.