Saida, Lebanon – Portraits of late Palestinian leader Yasser Arafat adorn the walls of Al-Hamshari Hospital in the southern Lebanese city of Sidon, and a large floor-mounted map of the Palestinian flag greets its patients and visitors.

Many patients come from the nearby Ain al-Hilweh camp, the largest Palestinian refugee camp in the country, relying on the discounted health-care services the hospital provides, thanks to the support of the Palestinian Authority.

Down the hall, the office of Dr. Riad Abu al-Ainain is bustling. Ainain is not just the hospital’s director but also a leader of the Palestinian movement Fatah in Lebanon. Fatah is the dominant party of the PA.

“In what respect I can serve our people, I will. If I will serve in Fatah, I will. If I have to serve in a hospital, I will,” Ainain told Al-Monitor from his office.

He is one of many leaders of various so-called Palestinian resistance movements operating from Lebanon. Among them are leaders of Hamas and other Palestinian armed groups that took part in Hamas’ Oct. 7 attack on Israel.

In Lebanon, Hamas and the Palestinian Islamic Jihad have joined forces with the Lebanese militant group Hezbollah under the umbrella of the Iran-led “axis of resistance” against Israel. In cooperation with Hezbollah, the groups have attacked Israel from Lebanon’s southern border, where clashes have been ongoing since Oct. 8.

Unlike Hamas and Islamic Jihad, Fatah has favored diplomacy with Israel over armed resistance since the 2000s, and has not announced its involvement in the fight against Israel at the Lebanese border.

However, according to Ainain, Fatah would join the war efforts in Lebanon’s south “when the time comes.” “If Israel invades Lebanon, we [Fatah in Lebanon] will announce that we would be the first front to defend the Lebanese and the Palestinian people,” he added.