MP George Galloway has been deported from Egypt after attempting to enter Gaza.
The Respect MP tried to cross the border into Gaza after members of the Viva Palestina convoy were arrested there.
He and collegue Ron McKay arrived at the Rafah border crossing which goes from Gaza into Egypt.
The two men were driven away and placed on a plane back to London by plain-clothed Egyptian police, a Viva Palestina convoy spokeswoman said.
She added: "As soon as they emerged on to Egyptian soil, both men were forcibly pushed into a van, refused exit and told that they were leaving the country. They were then driven off in a police convoy."
Mr Galloway was in the region leading an aid convoy of trucks to Gaza. Clashes between Egyptian police and the activists have been occuring since the convoy arrived earlier this week.
Several Palestinians have been hurt in the protests and an Egyptian policeman has been killed. Seven of the activists were arrested but then released without further charges.