A Wearside MP says she will not leave the party she loves after seven colleagues resigned from Labour.
A group of MPs have resigned to create a new Independent Group in the House of Commons, in the most significant split in British politics since the breakaway of the Social Democratic Party in the 1980s.
Chuka Umunna, Luciana Berger, Chris Leslie, Angela Smith, Gavin Shuker, Mike Gapes and Ann Coffey are among the MPs from the party's centrist wing who have been the loudest critics of Jeremy Corbyn's leadership, his stance on Brexit and his handling of allegations of anti-Semitism.
They issued an appeal to MPs from both Labour and other parties to "leave the old tribal politics behind" and join their new grouping.
None of the current political parties in Westminster "are fit to provide the leadership and direction needed by our country", they said.
And they pledged: "As an Independent Group we aim to recognise the value of healthy debate, show tolerance towards different opinions and seek to reach across outdated divides and build consensus to tackle Britain's problems."
However MP Bridget Phillipson, who represents Houghton and Sunderland South, has said she remains committed to the party although admitted she feels "sad" at the departures of her colleagues.
She said: "Today, above all else, I feel desperately sad. I owe so many of the chances I’ve had in life to the work of Labour activists and Labour governments.
"With our country in crisis, we urgently need another Labour government. I’m not leaving the party I love."
Ms Phillipson's colleague Sharon Hodgson, who represents Washington and Sunderland West, said in a statement: "This is a very sad day in the history of our party and whilst I respect and understand why the seven have reached their decision, for me the Labour Party is my party in the same way my family is my family and I can’t envisage any circumstances that would make me leave.
"I stood on a very strong and popular manifesto in 2017.
"A manifesto that would have changed the lives of the people I represent for the better.
"I respect the efforts of Jeremy Corbyn, who is trying to find a way through Brexit looking after and protecting the jobs and living standards of the people of Washington, Sunderland and the wider UK."
And Sunderland Central's Julie Elliott tweeted: "Today is a desperately sad day for the Labour Party - it's the party I love, believe in and have been a member of for 35 years - I will always be a member."
At a press conference at London's County Hall to announce the group's move, Mr Umunna issued an appeal to voters: "For far too long, political parties in Westminster - parties of which we have been a part - have been failing you.
"If you are sick and tired of politics as usual, guess what? So are we.
"If you want an alternative, please help us build it. The bottom line is this - politics is broken, it doesn't have to be this way. Let's change it."
In a call on other MPs to quit their parties, Mr Umunna said: "We've taken the first step in leaving the old tribal politics behind and we invite others who share our political values to do so too.
"You might come from a Labour background but you might come from other political traditions.
"Yes, it's a difficult decision - make no mistake about that.
"But you don't join a political party to spend years and years fighting the people within it. You get involved in politics, you join a party, to change the world.
"We invite you to leave your parties and help us forge a new consensus on a way forward for Britain."
Mr Leslie - a former shadow chancellor - said that Labour had been "hijacked by the machine politics of the hard left", while Ms Berger said she had come to the "sickening" conclusion that the party is now "institutionally anti-Semitic".
Mr Corbyn said he was "disappointed" at their decision.
"I am disappointed that these MPs have felt unable to continue to work together for the Labour policies that inspired millions at the last election and saw us increase our vote by the largest share since 1945," said the Labour leader in a statement.
"Labour won people over on a programme for the many not the few - redistributing wealth and power, taking vital resources into public ownership, investing in every region and nation, and tackling climate change.
"The Conservative Government is bungling Brexit, while Labour has set out a unifying and credible alternative plan. When millions are facing the misery of Universal Credit, rising crime, homelessness and poverty, now more than ever is the time to bring people together to build a better future for us all."
Ms Berger - who accidentally introduced herself as a "Labour Party MP", before correcting herself to "the Member of Parliament for Liverpool Wavertree" - said the decision to quit the party was "very difficult, painful, but necessary".
The MP, who has been the target of anti-Semitic abuse and was provided with personal protection at last year's party conference, said she had become "embarrassed and ashamed to remain in the Labour Party".
"I have not changed. The core values of equality for all, opportunity for all, anti-racism against all and social justice - the values which I hold really dear and which led me to join the Labour Party as a student almost 20 years ago - remain who I am," she said.
"And yet these values have been consistently and constantly violated, undermined and attacked, as the Labour Party today declines to my constituents and our country before party interests.
"I cannot remain in a party which I have come to the sickening conclusion is institutionally anti-Semitic."