The clash comes after Government lawyers said in court yesterday that Parliament would likely be given a vote on any final Brexit deal – a reversal in tone from previous pronouncements from the Prime Minister.
Labour has been pushing for a parliamentary vote on the opening terms of any Brexit negotiations, but Ms May has resisted such plans, saying there would categorically not be a vote.
The summit will be the first since Theresa May was appointed and since she pledged her support for a Hard Brexit restricting freedom of movement.
Britain and other EU nations are also set to confirm the CETA trade agreement with Canada at the summit.
It was revealed yesterday the Department for International Trade would not grant MPs a vote on the controverisal deal – described by activists as TTIP's 'little brother' – until it had already been signed.
Others issues likely to be raised at PMQs includ the Child Sexual Abuse inquiry and the resignation of its top judge.