Boris Johnson's sister has joined the Liberal Democrats - to fight against hard Brexit.

Rachel Johnson had hoped to campaign as a Member of Parliament for the party in the June 8 General Election, it is understood.

Her hopes were dashed, however, by a rule requiring candidates to have been members for at least a year.

Ms Johnson's move indicate signify deep differences within the family over Europe.

Last year, Foreign Secretary Mr Johnson was among the most high-profile advocates of Brexit.

His father, Stanley, a former MEP, sister Rachel and MP brother Jo all backed Remain.

Writing in her column in the Mail on Sunday last June, Ms Johnson said the result made her daughter cry, while her son's friends were blaming Boris for "stealing our futures".

She also wrote that Brexit "feels wrong to my stomach".

Ms Johnson joined the Conservatives in 2008 but left in 2011.

It is believed she approached former Lib Dem leader Nick Clegg in the past few days about possibly standing for the party.