including interior designer, lulu lytle who was not a member of number 10 staff but was there in downing street helping renovating boris johnson s flat. the organisers are understood to have laid on a cake and some m&s nibbles, with the gathering lasting some 20 30 minutes. the prime minister we are told only attended for around ten minutes. and they have denied reports he attended a later party with friends and family in the downing street flat. the leader of the opposition labour party has said the prime minister has to go. party has said the prime minister has to no. . . , party has said the prime minister hastouo. , ., . has to go. this is yet more evidence of a prime has to go. this is yet more evidence of a prime minister has to go. this is yet more evidence of a prime minister who has to go. this is yet more evidence of a prime minister who believes - of a prime minister who believes that the of a prime minister who believes that the rules that he made don t apply t