Complex sentence: The charter was signed by all attendees on 26 May, with the exception of Morocco whose delegation was present in an observatory capacity only, due to the attendance of Mauritania and the ongoing border dispute with that nation.
Split into simpler sentences: The charter was signed by all attendees on 26 May, with the exception of Morocco. Morocco's delegation was present in an observatory capacity only, due to the attendance of Mauritania and the ongoing border dispute with that nation.