A spokesman for Hamas has dismissed remarks by Ahmed Abu al-Gheit, the Egyptian foreign minister, that the Palestinian group's participation in a national unity government could thwart efforts to reach a settlement with Israel.
The reaction came on Sunday as the toll from Israeli air raids across the Hamas-governed Gaza Strip continued to rise.
Sami Abu Zuhri said al-Gheit's remarks were unacceptable and urged Egypt to retract them.
Abu Zuhri also rejected any Egyptian plan for a Palestinian public poll on a future draft agreement between the Palestinian Authority and Israel.
"The idea of a poll on any agreement signed with the occupying [Israeli authorities] is rejected by the Hamas movement," he said.
"No poll on the basic rights [of the Palestinian people]. Is it possible for us to carry out a poll on al-Quds [Jerusalem] if such an agreement affects our right in al-Quds?"
Abu al-Gheit had unveiled an Egyptian four-item plan to restore calm in the region.
It seeks to establish a ceasefire under which the firing of rockets in Gaza Strip has to stop while Israel also stops targeting Palestinians.
Other provisions include exchanging hundreds of Palestinian detainees in Israeli jails with Gilad Shalit, the Israeli soldier in Hamas' custody.
Egypt also wants the opening of Gaza's border crossings and to put a peace agreement, if reached this year, to a Palestinian public vote.
Renewed violence
The developments came as Israeli air raids that began on Saturday night killed eight people, most of them Hamas fighters, and wounded a number of people in Gaza.
Israeli jets struck again early on Sunday in northern Gaza.
An Israeli army spokeswoman confirmed that an aircraft had carried out a raid targeting Palestinian fighters in the area.
Hamas earlier acknowledged that four of its fighters were killed close to the Jabaliya refugee camp in one of the raids, and a fifth fighter died of his wounds later.
Two other fighters were killed in separate air attacks, Jacky Rowland, Al Jazeera's correspondent in Gaza City, reported.
Israel said the Palestinians had been planning to fire rockets across the border into southern Israel.
Hamas had carried out twin suicide bombings at an Israeli crossing on the Gaza border on Saturday, wounding more than a dozen Israeli soldiers.
Suicide assault
Saturday's attack was the second such incident at a cargo crossing from Israel into the Gaza Strip in the last 10 days.
Rowland said: "The Israeli army described the attack as complex, and clearly well planned in advance.
"This is clearly a new tactic that we're starting to see by the military wing of Hamas and the wing of Hamas has itself said that it plans to carry out more of these kinds of attacks in the coming days."
Within hours of the attack on the crossing, Israel launched an air raid in southern Gaza, targeting a car in Rafah.
One Palestinian - identified as a mechanic for the Hamas police force -was killed in the strike, and at least three other people injured, Palestinian security officials and medics said.
A member of Izz al-Din al-Qassam Brigades had been killed overnight and another injured in an Israeli air raid east of Gaza City, Palestinian medical sources and the Israeli military said on Saturday.
Sderot rockets
Separately, the Israeli military said rockets fired from Gaza temporarily knocked out electricity in the border town of Sderot.
The rockets were fired into Israel late on Friday by members of the Islamic Jihad group.
Palestinian fighters launch crude rockets at Israeli border towns almost daily.
The renewed violence in Gaza came shortly after Jimmy Carter, the former US president, met Khaled Meshaal, the exiled Hamas leader, in the Syrian capital Damascus, and the Israeli government announced plans to build 100 new homes in two illegal settlements in the occupied West Bank.
At least 425 people have died in violence since the resumption in November of Middle East peace talks between Israel and the Palestinians at an international conference last November at Annapolis, near Washington.
PHOTO CAPTION
Sami Abu Zuhri, left, has rejected Egypt's proposal and has asked Egypt to retract it.
Al-Jazeera