The meeting on Saturday came as Syria is facing international demands on another front as well - that it co-operate with a UN probe into the assassination of former Lebanese Premier Rafiq al-Hariri.
Amidst the pressure, Assad decided not to attend the world summit at UN headquarters in New York next week.
Al-Assad also received a US snub when it was announced in Washington on Wednesday that the Syrian leader would not get an invitation for a gathering of European and Middle Eastern leaders hosted by US Secretary of State Condoleezza Rice next week in New York.
In addition, the United States is putting pressure on Syria to make greater efforts across its border with Iraq to prevent what the US says are fighters "infiltrating" the country and to crack down on Palestinian resistance movements based in Damascus.
In Saturday's meeting in Damascus, al-Assad urged the Palestinian leaders - including Khaled Mashaal, the leader of Hamas's political bureau - to close ranks and continue the struggle in order to achieve their goal, Syria's official news agency SANA reported.
The Palestinian leaders expressed their "appreciation of Syrian support for the Palestinian cause and stressed their desire to restore their rights, especially the right of return," SANA said.