Luciana Berger said it was "an indication how well the Liberal Democrats are actually doing" that Chancellor Sajid Javid came to Finchley and Golders Green to boost support for her Tory rival Mike Freer.

After Mr Javid claimed on Wednesday that a vote for Ms Berger, who is contesting the north London seat for the Liberal Democrats, would help Jeremy Corbyn, she said: "On a very serious point, I stood in front of the country in February to announce I was leaving the Labour Party because I believed it to be institutionally antisemitic and because of its position on Brexit.

"If I did not believe Jeremy Corbyn should not be in Number 10, I would not then a few months later be involved with anything, or put myself forward for something that might in any way deliver Jeremy Corbyn to Number 10."

Mr Javid had arrived in Finchley on Wednesday for a brief visit to help promote Tory candidate Mr Freer's campaign - with polls suggesting he faced a battle to regain the seat on December 12.

Ms Berger said it was telling that Mr Javid had felt it necessary to name her as he made his claim about what voting Lib Dem in the constituency would mean.

"In the Finchley and Golders Green constituency Labour support has collapsed," said Ms Berger as she attempted to bolster claims that the Lib Dems were the party for opponents of Boris Johnson's Government to back.

Pointing to Labour's failure to tackle antisemitism, she said support for the party had sunk "not just amongst the Jewish community, but also with the neighbours of the Jewish community in Finchley and Golders Green who are appalled by what they have seen."

Ms Berger was joined on stage at Thursday's launch of the Lib Dems' equality and human rights policy in central London by her former Labour colleague Chuka Umunna, who also quit Labour for the Lib Dems.

He said Mr Javid would be better suited to a career as a "comedian" following her attack on Ms Berger.

Earlier at the event, Ms Berger said of the Labour leader: "By his actions, and by the platforms he's shared, and the people he has invited, and the things that he has done, and the things that he hasn't done, he's indulged in antisemitic activity."

Insisting Labour has a "serious racist problem", she added: "Jeremy Corbyn and his team have created a party machine which protects and normalises antisemitic ideas and individuals."

"Discrimination has no place in 21st century Britain. Unfortunately this is not the reality for too many in the UK.

"Jeremy Corbyn has inexcusably failed to root out antisemitism in the Labour Party and has betrayed the values of equality and anti-racism against all. The Tories are encouraging ugly nationalism."