Fine Gael MEP Brian Hayes is giving evidence to a House of Lords Committee inquiry in Brussels on the upcoming Brexit referendum.
The inquiry is meeting all political groups within the European Parliament, and Mr Hayes was selected on behalf of the EPP Group to give evidence.
"From an Irish point of view it's important that Britain remains in the EU", he said.
"Already the Taoiseach has fully supported the conclusion of a comprehensive agreement with Britain".
"I expect that agreement to occur at the February European Council Meeting here in Brussels".
"Britain leaving the EU would cause enormous disruption to British-Irish relations", he added.
A recent poll in the UK showed voters there were evenly split about whether Britain should leave the EU.
British Prime Minister David Cameron has given himself until the end of 2017 to hold the vote.