The leaders of the Tories and Ukip have refused to back a pledge to campaign for the rights of EU citizens signed by all the other mainstream parties.

Labour leader Jeremy Corbyn, Lib Dem leader Tim Farron, SNP Westminster leader Angus Robertson, Green co-leader Caroline Lucas and Plaid Cymru leader Leanne Wood have all signed up to the Home is Here pledge. The campaign asks candidates to commit to guaranteeing the rights of EU nationals.

More than a hundred candidates from different parties, including Labour's Clive Lewis and Jo Stevens, and Ukip's David Dews and Helena Windsor, have signed the pledge. One Tory candidate, Antoinette Sandbach, has signed up.

Lewis, who is the incumbent MP for Norwich South, and quit the shadow cabinet rather than vote to trigger Article 50, said: "It should shame us all that 3 million people who have built a home in this country are, as a result of Theresa May's posturing, being denied basic guarantees over their right to remain here.

"We need to end to this situation and send a clear message to EU nationals who make such an amazing contribution to Britain: 'You are welcome here'".

Since the vote for Brexit in June 2016, EU nationals, many of whom have lived in the UK for decades, are facing uncertainty about their future rights in their country of residence.

The Tory Prime Minister Theresa May has repeatedly said she is in favour of the right to remain, but has refused to commit to this until the same guarantees are received for British citizens living abroad.

However, May's unwillingness to act unilaterally has been blamed for causing widespread ill-feeling in Brussels.

Ukip generally does not sign third party peldges, but its manifesto promises to allow law-abiding EU citizens living in the UK before Article 50 was triggered the right to stay indefinitely.

The Conservatives have been contacted for comment.