FILE PHOTO: Protester hold placards, Saltires and EU flags during a demonstration to demand a vote on the Brexit deal between Britain and the European Union in Edinburgh, Scotland, March 24, 2018. REUTERS/Russell Cheyne

EDINBURGH (Reuters) - Scotland’s devolved parliament will hold its own vote on Britain’s European Union withdrawal deal before any such agreement is put to Britain’s national parliament, Scottish constitution minister Michael Russell said on Thursday.

A Scottish parliamentary vote would not be binding on the UK parliament but would potentially embarrass Prime Minister Theresa May, underscoring the low in relations between London and Edinburgh over Brexit and potentially feeding Scottish nationalism.

Britain voted overall 52-48 percent to leave the EU in 2016 but Scotland, one of its four nations, voted 62-38 percent to stay in the EU.

Britain is due to leave the EU in March and ministers say a deal is close. But Brexit talks are stalled due to a disagreement over the border between British province Northern Ireland and EU-member Ireland, and hampered by internal wrangling in May’s minority government.

Many, including Scotland’s First Minister Nicola Sturgeon, fear this could scupper an overall deal, hampering trade and causing economic uncertainty.

“On this most crucial of matters, Scotland must be and will be heard,” Russell told Scotland’s Holyrood parliament.

“If the UK government puts the option of staying in the EU single market and customs union on the table, we will commit ourselves to support it. We will reject every other option short of staying in the EU,” Russell said, spelling out the Scottish government’s commitment to the single market.

He added: “If a withdrawal agreement and political declaration are in the end concluded and offered to (Britain’s lower chamber) the House of Commons, then we make this commitment: before the Westminster parliament votes on that deal, the Scottish government will seek to ensure the Scottish parliament will pass its own judgment on it.”