BEIT-UL-MOQADDAS (AFP) — Former prime minister Tony Blair's sister-in-law says she is trapped in the Gaza Strip as Israel refuses to let her leave the Palestinian territory she entered aboard a protest boat.

Israeli authorities have rejected Lauren Booth's request to leave Gaza, arguing she did not enter legally when she and another 43 pro-Palestinian activists traveled by boat to the impoverished coastal strip in defiance of an Israeli blockade.
Booth asked over the weekend for authorization to leave Gaza through the Erez crossing with Israel. She was also prevented from crossing into Egypt through the Rafah crossing.
""Her request presented at the end of last week was rejected because anyone who does not enter officially cannot leave officially,"" said Gil Kari, spokesman for the Israeli military office in charge of liaison with Gaza.
Israel controls air and sea access to Gaza, where it imposed a crippling blockade after the Islamist Hamas movement seized power in the territory in June 2007.
""I'd actually like to say 'thank you very much' to the Israeli authorities at Erez for giving me this fantastic chance to feel just exactly what it is like to be inside what is effectively the world's largest internment camp, where individuals who should have the right to travel under international law are withheld in a 40 kilometre by 10 kilometre camp,"" Booth told the BBC.
She said three others were also prevented from leaving Gaza.
“It could be days, weeks or years before I can leave, depending on the mood of the Israeli authorities,” she told The Times, adding that she was upset she could not be with her children as they began the school year.
Ms Booth said that, after Israel's refusal, she and three others spent hours at the Rafah crossing waiting to cross before Egypt also refused her passage.
“We were down there on Saturday in an overheated bus for more than two hours with over 100 people in 90 degree heat,” she said, adding they spent nine hours in total on Saturday and 13 hours on Sunday trying to cross into Egypt.
Yigal Palmor, an Israeli foreign ministry spokesman, said: “No country in the world is required to allow a foreign national to enter its territory.""
An Egyptian official, who asked to remain anonymous, said: ""She was not refused. The crossing was only opened for humanitarian cases that were coordinated in advance by the PA
[Palestinian Authority]. Egypt is welcoming anybody at anytime, but not at the Rafah crossing point – which according to a 2005 agreement is being
[kept] closed.""
Most of the campaigners who had sailed to Gaza aboard two boats on August 23 returned to Cyprus five days later, although nine, including Booth remained in the Palestinian territory.
Jeff Halper, the only Israeli in the group, was held overnight by police upon his return to Israel through the Erez on August 26.
Booth's brother-in-law Tony Blair is currently on a week-long visit to Israel in his capacity as representative of the Middle East peace Quartet, which comprises the European Union, Russia, the United Nations and the United States.