Vince Cable seems keen to keep the issue of the Lib Dem leadership in the news.

Having survived a week of whispers about his tenure at the top of the party Cable is rumoured to be cooking up a scheme to open up the leadership of the Lib Dems to people other than MPs.

Cable has been under pressure after missing a crunch Brexit vote last week. A number of Westminster sources suggested he considered quitting after the incident. He failed to vote on a key amendment to the customs bill because he was at a dinner discussing the potential for a centrist anti-Brexit party. He was unable to explain himself further as he claimed the talks were 'confidential'. Having tried to position the Lib Dems as the only avowedly anti-Brexit party Cable was among three Lib Dem MPs missing for the vote which the government won by a margin of three.

A plot to replace him with rising star Layla Moran fizzled out after she insisted she was more interested in working on her slender majority in her Oxford West and Abingdon seat.

But rather than keep his head down a Cable plan to change Lib Dem rules so people other than MPs can lead the party has emerged. According to reports in The Mirror Cable is looking to Canada for inspiration and wants to "open doors" to more people by amending the party's constitution which currently demands the leader is an MP. The move may in part be prompted by the limited field of MPs Lib Dems currently have to choose from. Any future leadership contest is likely to be between Layla Moran and current deputy leader Jo Swinson.

Gina Miller, who led the successful court challenge to force a parliamentary vote on Brexit, has been tipped as a potential candidate should the leadership be opened to those outwith parliament. She has spoken at Lib Dem events in the past but isn't known to have shown any interest in getting elected.

Willie Rennie has been a success as leader of the Scottish Lib Dems and would be in the running to take over the party nationally. The only Lib Dem currently in government is Kirsty Williams, the party's sole representative in the Welsh Assembly where she also serves as education secretary.

The changes, which are bound to prove a talking point at Lib Dem conference in September, are unlikely to receive a warm welcome. One Lib Dem source described them as "a crackpot idea."