David Cameron's official spokesman sidestepped repeated questions from reporters whether the Prime Minister was "confident" that Universal Credit would be delivered on time and on budget.
He said: "The department is working to the 2017 timetable. That is the timetable that the department continues to work to."
Pressed on whether it was right for ministers, rather than senior officials, to take responsibility for failings in implementing major policies, the No 10 spokesman said the Prime Minister had previously insisted that "everyone has to take their responsibility."
More top news
Dippy the Diplodocus is to forced into retirement and moved out of the Natural History Museum's main hall.
Alice Biggar has managed to survive on cheap tins, heavily-reduced supermarket goods and even chicken bones from butchers.
People should go online to report crimes instead of dialling 999, Home Secretary Theresa May has claimed.