The Rafah crossing on the border between Gaza and Egypt was opened last month under a deal arranged by Condoleezza Rice, the US secretary of state, in hope of stirring an economic revival in the coastal strip that Israel had quit after 38 years of occupation.
European Union supervision over the Rafah crossing was a compromise agreed upon to alleviate Israeli fears of an influx of foreign fighters and arms to the Gaza Strip.
The chief of the Popular Resistance Committees (PRC), an umbrella group of Palestinian fighters waging a five-year-old uprising against Israel, said he had been denied permission to travel for the Muslim haj pilgrimage to Saudi Arabia.
In a statement posted on his website, the PRC leader, Jamal Abu Samhadana, quoted a Palestinian official as saying the EU monitors at Rafah had "banned" him from leaving Gaza.
"He also told me those monitors could order Palestinian policemen to arrest me because I was a fugitive," said Abu Samhadana, who is high on Israel's wanted list.
A PRC spokesman threatened that the group's fighters would blast a path through the concrete barricades along the Gaza-Egypt border if the ban was not rescinded by the Muslim feast of Eid al-Adha on 10 January.
EU officials could not immediately be reached for a comment. Nazmi Mahana, the Palestinian Authority official in charge of the Rafah terminal, declined to comment.
Rafah terminal is Gaza's gateway
to the outside world
The PRC's protest was echoed by Palestinian groups Hamas and Islamic Jihad, each of which said one of its field commanders had been barred from crossing Rafah.
Hamas sources said Ahmad al-Jaabari, believed to be the second-in-command of the group's armed wing, had been turned back at Rafah by Palestinian security officers.
"They banned him, citing the diplomatic pretext that they cared for his safety," the source said.
Islamic Jihad said its military commander, Khalid al-Dahduh, had been also blocked, and vowed to support any PRC attack on the border barricades.
Under the deal arranged by Rice, Israeli officials watch the Rafah crossing via videolink and can ask the EU monitors to detain any Palestinian deemed a possible security threat.
Israel has accused the Palestinian Authority of not passing full details on those using Rafah, a charge that it has denied.
Palestinian security sources said political leaders of Hamas and Islamic Jihad had been allowed to leave Gaza through Rafah for the haj pilgrimage.