Jerusalem ? Israelis and Palestinians neared agreement Friday on disarming Palestinian militants ahead of a summit with President Bush, but security remained a key issue — as underscored by a U.S. Embassy warning that it has received “credible reports” of plans to kidnap U.S. citizens in Gaza.

The Israelis have demanded Palestinian Prime Minister Mahmoud Abbas crack down on militant groups in the West Bank and Gaza who are responsible for attacks against Israelis. Abbas says he prefers using persuasion to stop the attacks and has been working to negotiate cease-fires with the groups.

The sides said Friday they would be willing to accept a combination of the two plans.

The U.S. Embassy announced it had received “credible reports” of plans to kidnap U.S. citizens in the Gaza Strip, underscoring the danger in the region.

“At this time, Americans are advised to be particularly cautious,” the Embassy said on its Web site, adding that citizens should also follow earlier recommendations to defer travel to Israel, the West Bank and Gaza.

The Islamic militant groups Hamas and Islamic Jihad are mainly based in Gaza. Both groups have claimed responsibility for scores of attacks in Israel that have killed more than 350 people in more than 2 1/2 years of Israeli-Palestinian violence.

Security has been a main sticking point ahead of Abbas’ and Sharon’s meeting with Bush, which is planned for Wednesday at the Jordanian resort of Aqaba. The Palestinians want Israel to clearly endorse their right to statehood at that meeting.