LONDON, ENGLAND - JULY 20:  New Liberal Democrats party leader Vince Cable holds a press conference at the St Ermin's Hotel on July 20, 2017 in London, England. The Liberal Democrats have announced Vince Cable as their new party leader. Previously Secretary of State for Business, innovation and Skills under the coalition government, Mr cable replaces the previous leader Tim Farron who resigned after the last general election.  (Photo by Leon Neal/Getty Images)
LONDON, ENGLAND - JULY 20:  New Liberal Democrats party leader Vince Cable holds a press conference at the St Ermin's Hotel on July 20, 2017 in London, England. The Liberal Democrats have announced Vince Cable as their new party leader. Previously Secretary of State for Business, innovation and Skills under the coalition government, Mr cable replaces the previous leader Tim Farron who resigned after the last general election.  (Photo by Leon Neal/Getty Images)
LONDON, ENGLAND - JULY 20:  New Liberal Democrats party leader Vince Cable holds a press conference at the St Ermin's Hotel on July 20, 2017 in London, England. The Liberal Democrats have announced Vince Cable as their new party leader. Previously Secretary of State for Business, innovation and Skills under the coalition government, Mr cable replaces the previous leader Tim Farron who resigned after the last general election.  (Photo by Leon Neal/Getty Images)
LONDON, ENGLAND - JULY 20:  New Liberal Democrats party leader Vince Cable holds a press conference at the St Ermin's Hotel on July 20, 2017 in London, England. The Liberal Democrats have announced Vince Cable as their new party leader. Previously Secretary of State for Business, innovation and Skills under the coalition government, Mr cable replaces the previous leader Tim Farron who resigned after the last general election.  (Photo by Leon Neal/Getty Images)
LONDON, ENGLAND - JULY 20:  New Liberal Democrats party leader Vince Cable holds a press conference at the St Ermin's Hotel on July 20, 2017 in London, England. The Liberal Democrats have announced Vince Cable as their new party leader. Previously Secretary of State for Business, innovation and Skills under the coalition government, Mr cable replaces the previous leader Tim Farron who resigned after the last general election.  (Photo by Leon Neal/Getty Images)