European Union leaders are gathered in a centuries-old castle in the middle of their fractious continent, hoping to find a sense of common purpose again in the face of the planned departure of Britain and fundamental disagreements over everything from uncontrolled migration to the economy.

The 27 leaders, minus British Prime Minister Theresa May, hoped to find the broad outlines of a new "Bratislava roadmap" during their daylong talks in the Slovak capital that should lead to a new start following the shock British referendum result in June.

Slovak Prime Minister and summit co-host Robert Fico said that "we all want to show unity and we all want to show that this is a unique project and we need to continue."