RAMALLAH, West Bank, May 15 (Reuters) - Standing up to Israel through non-violent resistance can produce encouraging results, Palestinians said on Tuesday, after a prisoner hunger strike produced some Israeli concessions.

The deal under which some 1,600 Palestinian prisoners agreed on Monday to end a month-long fast against Israel's prison policy was struck on the eve of Nakba (catastrophe) Day that marks Israel's founding in a 1948 war when hundreds of thousands of Palestinians fled or were driven out of their homes.

Youths clashed with Israeli police and soldiers in several parts of the occupied West Bank on Tuesday, but there was no repeat of last year's violence, when Israeli soldiers killed up to 13 protesters on the borders with Syria, Lebanon and Gaza.

To some, the hunger strike proved the value of "popular resistance" as favoured by President Mahmoud Abbas and his Fatah group. But his rivals in the Islamist Hamas movement in Gaza said their own confrontational attitude had paid dividends.

Two of the Palestinian prisoners had not eaten for 77 days, raising fears of a backlash if they had died. Under a deal brokered by Egypt, Israel agreed to end solitary confinement for 19 prisoners and lift a ban on visits by relatives living in the Hamas-ruled Gaza Strip.

It also agreed to free those held without trial for six months at a time under so-called "administrative detention" -- unless they are brought to court before their terms end.

"It is our hope that this gesture by Israel will serve to build confidence between the parties and to further peace," said Mark Regev, a spokesman for Prime Minister Benjamin Netanyahu.

Some Palestinians said Israel was used to meeting violence with violence, but less adept at countering non-violent tactics.

"The prime lesson here is that resistance, unity and solidarity can bear fruit for the political movement," said West Bank political analyst Hani Al-Masri. "Resistance, unity and determination can bring about results."

LESSON FOR POLITICIANS

Gaza Strip political analyst Hani Habib called it "a success for the prisoners and an example that should be copied by the politicians," alluding to continued deep divisions between Hamas and Fatah that have split the Palestinian people.

"We should reshape the relationship with Israel, in the sense that we should benefit from steadfastness and defiance. Steadfastness can win positions and gains, regardless of how unequal in power we are in comparison with the occupation."

Despite the suspension of formal peace negotiations 18 months ago, Abbas cooperates closely with Israel on security.

Top-level contacts "every hour, every moment" helped to resolve the impasse, said Palestinian negotiator Saeb Erekat.

"We spared no means and no effort ... and (Abbas) managed to get everyone to intervene including the American administration whom we had contacted," Erekat said.

Anat Litvin of the activist group Physicians for Human Rights-Israel said: "The Palestinian inmates proved that a non-violent and just struggle can bring important achievements and raise international awareness."

The hunger strikers included militants from Hamas and Islamic Jihad, which reject peace with Israel, as well as members of Abbas's Fatah group which recognises Israel and is prepared to negotiate a comprehensive peace settlement.

Israel's Prisons Authority asked prisoners to pledge "not to engage in actions contravening security inside the jails".

But Israel made no undertaking to scrap administrative detention without trial, under which some 320 of 4,800 Palestinian prisoners are held. It also refused to treat Palestinians as "prisoners of war". Many prisoners have been convicted in Israeli courts of serious crimes, including murder.

Hamas claimed credit for the Israeli concessions, suggesting its commitment to violent methods was the decisive factor.

A Hamas statement said Israel's will began to break last year when it agreed to free 1,000 Palestinian prisoners in exchange for Gilad Shalit, an Israeli soldier who was captured in a cross-border raid and held for over five years in Gaza.