European Commission President Jean-Claude Juncker welcomes British Prime Minister Theresa May in Strasbourg, France March 11, 2019. REUTERS/Vincent Kessler/Pool

LONDON (Reuters) - British Prime Minister Theresa May has clinched changes to her Brexit deal in her bid to win last minute support for her Brexit deal before it goes to a vote on Tuesday, senior minister David Lidington said on Monday.

May has secured “legally binding changes that strengthen and improve the Withdrawal Agreement and Political Declaration,” Cabinet Office Minister Lidington, who is May’s de facto deputy, told parliament.

Lidington said the sides had agreed a joint legally binding instrument on the Withdrawal Agreement and Protocol on Northern Ireland that confirms the EU cannot try to “trap” the United Kingdom in the Irish backstop indefinitely.

“The EU cannot try to trap the UK in the backstop indefinitely, and that doing so would be an explicit breach of the legally binding commitments that both sides have agreed,” Lidington said.

They have also agreed a joint statement to supplement the Political Declaration, Lidington said.