The British parliament's due to hold another round of votes later - as MPs try to find a majority to solve the issue of how the UK should leave the EU.
Prime Minister Theresa May's withdrawal deal has been defeated three times already.
Today, MPs could back a 'softer' version of Brexit.
Eight options have been tabled for Monday's indicative votes, including a no-deal Brexit, a customs union and a people's vote.
House of Commons Speaker John Bercow will select which options will be part of the fresh vote later.
Meanwhile, a Sinn Féin delegation is travelling to Brussels today to meet chief EU Brexit negotiator Michel Barnier and other European leaders.
Party leader Mary Lou McDonald says they are seeking assurances the EU will continue to act in the interests of Ireland in the result of any crash-out by the UK.
Speaking from a border protest in Co Louth at the weekend, Deputy McDonald said Ireland cannot be collateral damage to Westminster.
"What we have built here through the Good Friday Agreement is so precious - our peace and our stability is so precious - that we cannot and we will not stand idly by as Tory wreckers seek to upend and destroy all of that.
"That cannot happen.
"And I don't believe that decent people right across the island of Britain, decent English people, would for a second wish that to happen".