Israeli and Palestinian leaders reported no progress at a tense summit in Egypt aimed at halting 19 days of bloodshed.
Meanwhile fresh violence flared in the West Bank and Gaza.
President Clinton launched the emergency meeting with a plea for peace, but a meeting of foreign ministers later broke up in acrimony.
Clinton met Israeli Prime Minister Ehud Barak for about an hour and then held separate talks with Palestinian President Yasser Arafat.
Israel says Barak is close to forming a national unity government with right-wing politician Ariel Sharon, accused by Arabs of igniting the current wave of violence.
A Palestinian policeman was shot dead in a gunfight with Israeli soldiers near the Egyptian border and dozens of people were wounded in extensive clashes in the Gaza Strip and West Bank towns.
Thousands of Arabs and Iranians took to the streets in Middle East capitals to denounce the peace summit.
In Tehran and Baghdad Iranians and Iraqis protested and volunteered for a holy war against Israel.
Israeli officials said that Hizbullah leader Sheikh Hassan Nasrallah may be telling the truth when he says an Israeli businessman and reserve officer was lured to Lebanon and captured there.