GAZA (Reuters) - Hamas swept seven out of 10 councils in the Gaza Strip´s first local elections, seen as a test of strength between the Islamic militant group and new President Mahmoud Abbas, final results showed on Friday.

The Islamists, sworn to Israel´s destruction, had boycotted the Jan. 9 presidential election, won by Abbas on a platform of ending violence to allow talks with the Jewish state on Palestinian statehood.

"Hamas´s victory proves Islam is the solution," blared a slogan from loudspeakers as thousands of supporters celebrated in the streets beneath fluttering green Hamas flags.

A U.S. White House official said Washington was concerned Hamas could use their elected posts to influence Abbas´s policy toward peacemaking with Israel.

Abbas has been trying to win a cease-fire from Hamas and other militants spearheading a 4-year-old revolt to allow the resumption of talks with Israel and to avoid chaos in Gaza ahead of an Israeli plan to abandon the occupied territory.

"Our people have a consensus on the choice of jihad and resistance and the election has underscored that concept," Hamas spokesman Muhir al-Masri told reporters.

Hamas candidates won 75 of the 118 council seats compared to 39 for members of Abbas´s Fatah movement and their allies, final figures from the electoral commission showed.

Voter turnout topped 80 percent -- much higher than at the presidential election for a successor to Yasser Arafat.

But while the results were a blow to Fatah, they also raise the prospect that Hamas will join parliamentary elections in July and thereby shift closer to the political mainstream.

"The results showed that our people are insisting Hamas take part in the upcoming ballot," said spokesman Sami Abu Zuhri.

U.S. CONCERNS

A senior State Department official said only Abbas´s government policies mattered and Hamas members were "not people we need to deal with, or have to deal with."

But another Bush administration official said the results were a worry.

"It´s always a concern and disturbing that people affiliated with a group espousing violence achieves some success," said the official who asked not to be named. "It is now an open question how much impact these individuals will have on the general political scene."

Hamas, which has killed hundreds of Israelis in suicide bombings, has won many hearts in Gaza not only for its role in the fighting but also for its charity work for the needy in the absence of welfare support from the crumbling Palestinian Authority.

Political analysts say that by taking part in the municipal elections, Hamas is also demonstrating its claim to a share of power ahead of Israel´s planned withdrawal of Jewish settlers from Gaza.

Palestinian analyst Hani Habib said Hamas´s show of power could make the group more eager to join Abbas´s political agenda, including a militant truce with Israel, in order to try to boost its political status among the Palestinians.

"Hamas´s landslide victory will encourage it more because now it feels stronger and it will (be encouraged) to make difficult decisions while it is strong," he said. "Hamas will be involved in (Abbas´s) plan from a position of strength."

Senior Hamas leader Mohammed al-Zahar told reporters in Gaza that the group would still not accept a cease-fire until Israel agreed to carry out more of their demands. Israel has already said it would reduce military raids and assassinations of militant leaders in response to Abbas´s efforts to end attacks. (Additional reporting by Steve Holland in Washington) (© Reuters 2005 01/28/05)