Brexit news: Boris Johnson attacked by Rees-Mogg (Image: GETTY) The former Foreign Secretary has emerged as the leading candidate to replace Theresa May as party leader. However, speaking on Peston, newly-elected Brexit MEP, Annunziata Rees-Mogg has poured cold water over Mr Johnson’s bid to become the next Prime Minister. Ms Rees-Mogg, who left the Tories to join Nigel Farage’s Brexit Party, has questioned whether Mr Johnson will deliver on his Brexit promises. Related articles Brexit bombshell: Commons can still block no deal EU exit Boost for Boris! Theresa May’s former right-hand man backs Brexiteer Speaking to Peston, Ms Rees-Mogg said: “We’ve heard it all before but nothing has been delivered. “Theresa May said all the right things as far as Brexiteers wanted but didn’t deliver any of them. “We need to see what happens.” Mr Johnson has insisted that the UK should leave on October 31 with or without a deal. READ MORE: Brexit blow: Boris Johnson savaged by Remainer Hammond Brexit news: Annunziata Rees-Mogg attacked Mr Johnson (Image: ITV) Speaking at the launch of his leadership bid on Wednesday Mr Johnson insisted that the UK must leave in October in order to prevent the mood of “disillusion” and “despair” in the country from spreading. Moreover, Mr Johnson has also previously stated that he is the only contender who can stop Jeremy Corbyn from getting into Number 10 and putting Mr Farage “back into his box”. Speaking at his launch Mr Johnson said: “We cannot ignore the morass at Westminster where parties have entered a yellow box junction, unable to move forward or back, while around the country there is a mood of disillusion, even despair, at our ability to get things done. “The longer it goes on the worse the risk that there will be serious contamination and loss of confidence because the people of this country deserve the best from their leader.” READ MORE: Prince Andrew becomes latest royal to break protocol with Brexit talk Related articles Wild Bill on ITV: Rob Lowe promises insight into Brexit Britain Nigel Farage compares Boris Johnson to Churchill for this quality The Tory leadership race (Image: Express) Brexit news: Boris Johnson has insisted that he can stop Mr Corbyn and mr Farage from entering Numbe (Image: GETTY) The former Foreign Secretary has amassed support from over 70 MPs as he has become the leading candidate in the race. Speaking in support for Mr Johnson, Brexit Secretary, Steve Barclay insisted that Mr Johnson is the only man capable of “defeating both Mr Corbyn and Nigel Farage”. Although unwilling to withdraw a no deal Brexit from the negotiating table, Mr Johnson added that it is a "vital" negotiation tool and the UK "must do better" than the current deal. Fellow contender, Sajid Javid, however, attacked Mr Johnson as he also launched his campaign on Wednesday as he called the former Foreign Secretary "yesterday's news”.All rights reserved for this news site express.co.uk and under his responsibility