Jeremy Corbyn has allowed a “toxic culture” to divide the Labour movement, according to more than 60 Labour peers who have taken out a newspaper advertisement to criticise his governance.
The full page ad has accused him of “failing the test of leadership” amid an internal scrap over antisemitism.
It said the division has prompted the resignation of thousands of members.
“We are saying you are accountable as leader for allowing antisemitism to grow in our party and presiding over the most shaming period in Labour's history,” it said.
“We can't be a credible alternative government that will bring the country together if we can't get our own house in order.”
The ad is signed by 67 Labour members of the House of Lords, including Peter Hain, Peter Mandelson and Robert Winston, and addressed Mr Corbyn directly.
“Your failure to do the right thing will lead to the failure of the Labour Party being able to make our country a better place for the people and communities we seek to serve,” it said.
“The Labour party welcomes everyone* irrespective of race, creed, age, gender identity, or sexual orientation. (*except, it seems, Jews). This is your legacy Mr Corbyn.”
The Labour leader has been under increased pressure since a BBC programme claimed senior Labour figures interfered in antisemitism investigations.
Labour has denied the allegations and written a letter of complaint to the broadcaster.
In Monday’s talkRADIO debate, both Boris Johnson and Jeremy Hunt suggested Mr Corbyn was antisemetic.