Swiss politician Joseph Zisyadis is among 11 European members of parliament who left Cyprus on Friday to try to break the blockade of Gaza.
The 11 are sailing on a boat chartered by the US-based Free Gaza Movement, which is also carrying a tonne of medical supplies and three scanners for hospitals there .
Israel has subjected Gaza to a tight blockade since the radical Islamic group Hamas took control of the area in June 2007. The Gaza Strip is home to about 1,500,00 people. According to many non-governmental organisations, the territory is receiving practically no medical supplies.
In addition to Zisyadis, a member of the small left-wing Party of Labour, the other politicians on the boat come from Ireland, Italy and Britain.
British Labour MP and former minister, Clare Short, said the Israelis had refused the group permission to enter Gaza by land via the Rafah crossing point on the Egyptian border.