THE TOP UK civil servant tasked with finding a solution to the Irish border issue post-Brexit has quit his job.

Simon Case is leaving his role to become Prince William’s private secretary, the Guardian is reporting.

Case served as director general of Northern Ireland and Ireland in the British Department for Exiting the EU for the last three months. He is set to be replaced by his deputy, Brendan Threlfall.

Case previously worked in Brussels and served as principal private secretary to Conservative prime ministers David Cameron and Theresa May.

He said it had been a “great privilege” to work as part of David Davis’ Brexit department but that he was looking forward to the”unique opportunity” to work with Prince William.

Brexit negotiations between European and British officials are continuing in Brussels today. Yesterday Davis, the Secretary of State for Exiting the European Union, said the UK government “remains steadfast” in its commitment to avoid a hard border between the Republic and Northern Ireland after Brexit.