Al-Qaeda posted an online video Thursday showing hijackers who took part in the September 11, 2001 suicide attacks.

Salim al-Hazmi and Khalid al-Mihdar, two of the 19 terrorists who hijacked the four airliners, appeared reading their wills, in a video produced by the As-Sahab media arm of Al-Qaeda and provided by the US-based SITE Monitoring Services, AFP reported.

"Arab leaders... have gone far in betraying their nation and have permitted Christian Americans into the land of the two holy sites" of Mecca and Medina, Mihdar said in the video.

The operation was "part of jihad (holy war) campaign against the United States and its supporters," said Hazmi in a separate message, according to AFP. 

"It is to restore dignity for Muslims and to drive you out of the Arabian Peninsula," Hazmi added.

"The Aqsa mosque (in Jerusalem) is being desecrated... and the Arabian Peninsula is full of US and British troops that fight Allah," he said.

Nearly 3,000 people were killed when Al-Qaeda hijackers slammed two airliners into New York's World Trade Centre. 

Another plane hit the Pentagon, while the fourth slammed into a field in Pennsylvania after passengers fought the hijackers.

The two attackers appeared in a video titled "The Emerging Sun of Victory Over the Victorious Ummah and the Vanquished Crusades," which comprises mainly of another audio message by Al-Qaeda's leader Ayman al-Zawahiri slamming Muslim countries for being unable to defeat Israel.

"These governments cannot liberate Palestine. In fact, they are helping in keeping occupation in Palestine," he said, condemning the new Arab governments run by Islamists for "declaring that they will keep (peace) agreements" with Israel.

Two days ago, on September 11, the terrorist network released another video declaring the United States is at war with Islam and that American Muslims should prepare for a “holocaust.”

The video came a day after Zawahiri confirmed the death of his deputy, Abu Yahya al-Libi, who was killed in a drone strike in June.