US envoy Anthony Zinni is meeting Yasser Arafat at the Palestinian leader's besieged compound.
He's the first official permitted to meet with Arafat since Israel confined the Palestinian leader to a few rooms in his headquarters last week.
Journalists have been barred from covering the meeting. Israeli soldiers fired tear gas and stun grenades at a group of 30 reporters who approached the compound.
A tank swerved, pointing its barrel at the reporters.
The meeting comes a day after US President George W Bush demanded Israel halt incursions into Palestinian territory and withdraw from areas already seized by Israel.
Israel had initially refused to permit Mr Zinni to see the Palestinian leader insisting on his complete isolation.
Ceasefire talks broke down last week, after a terrorist blew himself up in an Israeli hotel, killing 26 people participating in a Passover Seder, a ritual meal ushering in the start of the Jewish holiday.
The bombing was followed by more attacks on Israeli civilians and Israel vowed it would not end its campaign until it had crushed militant Palestinian groups.