Biography

He was born in Haifa Palestine, in 1939. One of founding members of Fatah، the biggest faction of the PLO. The first Palestinian Ambassador to Iran, following the revolution. During the 70s he led the indirect negotiations between the PLO and the United States.
Although opposed to the Oslo agreement, Al Hassan was appointed by Arafat as the Minister of Interior. Following the collapse of the Palestinian Israeli negotiations in Camp David in 2000,
He  studied engineering in the late 1950-60s in Darmstadt. During his time in Germany he founded Shabab al Aqsa movement, to compete in student elections. He joined the Muslim Brotherhood in early 1950s. West Germany (Darmstadt and Munich), where he worked through the General Union of Palestinian Students (GUPS) in Europe, and acted as Fatah’s main European link after he merged his own commando group to Fatah between 1963 and 1967.
He also served as President of GUPS from 1962. He is the younger brother of Khaled al-Hassan, He spent time as a refugee in Yarmouk camp, near Damascus,

Al Hassan returned to Gaza in 1995 and began to act as the head of Foreign Relations in Fatah and a political adviser to Arafat. He served as regional head in Jordan briefly in early 1970, then as Salah Khalaf’s deputy in Rasd, along with being a central committee leader during this time period.Beginning in 1974, he acted as a political aide to Yasser Arafat, an ambassador to Tehran, and became an ambassador to Amman in 1982.
He retains good ties to the Gulf States. He became a member of Fatah-Central Committee in May 1980. He was critical of the leadership's stance towards Iraq after August 1991, and at Oslo, but returned to Gaza Strip in November 1995, and became the chief political adviser to Arafat as well as PLO-CC member & head of the Palestinian National Council foreign relations committee. He was appointed Interior Minister on 29 October 2002.
Mahmoud Abbas attempted to drop him from the PA cabinet, and despite Arafat's resistance, he was replaced in April 2003. He is slated to act as Arafat's national security adviser. Al Hassan was head of Fatah's Bureau of Mobilisation and Organisation and (maktab at-ta`bia wat-tandhim) until April 2007, when he was replaced in that role by Ahmed Qurei. Al Hassan went on to become a National Security Adviser but was dropped by Mahmoud Abbas in June 2007, following his comments made on Al Jazeera.
Following Hamas' takeover of Gaza in June 2007, Hassan caused a major row in Fatah by giving an interview on Al-Jazeera in which he said that there had been no conflict between Hamas and Fatah but rather a conflict between loyal Palestinians in both camps and a small minority in Fatah who were preparing a coup to overthrow Hamas with American backing.