Clashes between radical Shia militiamen and government forces entered their second day on Wednesday, raising fears that a seven-month-old ceasefire observed by the powerful Sadrist movement might be disintegrating.

Spokesmen for movement’s leader Muqtada al-Sadr continued to call for a negotiated solution, and the US military said that the fighting so far only appeared to involve ”breakaway” factions that defy Mr Sadr’s authority.