The Palestinian national anthem gives the impression of nationhood and unity but it belies long-running tensions between rivals Fatah and Hamas. Security was tight in the West Bank city of Bethlehem as Fatah delegates gathered for an historic congress, its first in 20 years.However, some 400 delegates who live in Gaza were banned by Hamas from travelling to the conference. Gaza’s rulers said it was because Fatah refuses to discuss the release of jailed Hamas activists. Hamas spokesman Fawyi Barhoum said: ‘‘Fatah have refused to take part in any national, regional, and Arabian negotiations to release Hamas prisoners in the West Bank. The convening of this congress coincides with an unprecedented media campaign by Fatah against our leaders in the West Bank, this will make starting dialogue again even more difficult and more complicated.’‘ Fatah was founded in 1965 under its late leader Yasser Arafat. Like Hamas, the group’s founding charter calls for the destruction of Israel, although under Arafat the faction moved towards peace talks with the Israelis. Despite promising reform Fatah officials say they have no plans to change the charter.