Israel's decision to permit two boats carrying international activists to sail into Gaza harbour has raised fears that human-rights groups will make additional attempts to sail into the Strip to protest the Israeli blockade.

Professor Jeff Halper, an Israeli participant, told the JC from Gaza that the group's ultimate plan was to establish a regular ferry service between Cyprus and Gaza and to recruit other ships.

"The purpose of our mission was to break the siege on Gaza, which is a siege against a civilian population," Mr Halper said. "As an Israeli I participated so I could then bring a message to my people that we have to start taking responsibility for what we are doing."

A hero's welcome: well-wishers turn out to greet the Free Gaza boats as they arrive in the harbour

Access to Gaza via the sea has been limited since Israel's withdrawal in 2005. The waters are patrolled regularly by Navy gunboats and Palestinian fishermen are allowed to sail up to six miles from shore.

The two boats - named SS Free Gaza and SS Liberty - docked on Saturday afternoon after Prime Minister Ehud Olmert and Defence Minister Ehud Barak concluded that Israeli intervention would cause diplomatic damage. The Foreign Ministry said the activists' real goal was "media provocation".

The IDF initially opposed permitting the boats to arrive in Gaza out of fear that the precedent will open the door for additional boats as well as Palestinians wanting to leave the Strip.

"If it does happen it will be very difficult to stop the boats after letting these two in," said one official.

The ships were loaded with hearing aids, balloons and 45 activists, including Lauren Booth, sister-in-law of former UK prime minister Tony Blair. As they entered the Gaza port, the boats were met by flag-waving Palestinians as well as armed Hamas militiamen.

Israel, however, does not plan to allow additional boats into Gaza, fearing the vessels will be used by Hamas to smuggle in weapons, usually brought in via tunnels under the Gaza-Egyptian border. "What we did is not a precedent," said Foreign Ministry spokesman Aryeh Mekel. "It was an ad hoc decision and other cases will be evaluated if and when they happen."

On Thursday, the boats were to return to Cyprus with several Palestinian scholars who had been awarded scholarships abroad but were denied the right to leave Gaza.