BRUSSELS (AFP) - The European Union said on Saturday it deplored the loss of life in Egypt and was following developments there with concern after deadly clashes in Cairo between protesters against the interim military-backed government and police.

EU foreign affairs head Catherine Ashton said the authorities should ensure a speedy transition to civilian rule and repeated demands that political detainees, including President Mohamed Mursi who was ousted by the army on July 3, should be released.

A spokesman said Ms Ashton "deeply deplores the loss of life" after reports that dozens or more of Mr Mursi's supporters were shot dead in the Egyptian capital early on Saturday as violence erupted after a night of massive rallies for and against the ousted Islamist president.

Ms Ashton called on all sides to avoid violence, stressing that the "only solution is a rapid move to an inclusive transformation process", adding that "all political groups", including Mr Mursi's Muslim Brotherhood, must be involved.