The Department for Exiting the European Union (Dexeu) said Lord Martin Callanan was replacing Baroness Joyce Anelay as its minister of state.
In a statement today Dexeu said Anelay, who was appointed in June, was to be replaced by Callanan, who spent 15 years as a member of the European parliament (MEP). He has also previously served as the parliamentary under-secretary of state of aviation, internation and security at the department for transport.
"Joyce has made an invaluable contribution to ensuring a successful departure from the EU through her work representing Britain abroad, and representing the Department in the House of Lords," said David Davis, the secretary of state for exiting the European Union.
"She’s been a great part of our Ministerial team and a good friend. I wish her all the best as she returns to the back benches where she will bring an unparalleled level of experience to the task of scrutinising Brexit legislation on its way through the House of Lords.
"I’m delighted to welcome Lord Callanan to the department — he brings with him a wealth of experience in Brussels and a proven ability in political leadership. I look forward to working together as a Ministerial team to continue delivering the important task of negotiating our exit from the European Union and making a success of Brexit."
The move means Dexeu has now lost three senior ministers: David Jones was replaced by Anelay as minister of state after the election in June, while Lord Bridges quit shortly afterwards.