The Hamas-led Palestinian government is calling for a prisoner swap with Israel to resolve the tense standoff over a captured Israeli soldier.
A statement from the Palestinian Information Ministry Wednesday proposed the exchange just hours after Israeli forces entered southern Gaza and carried out airstrikes on several targets.
So far, no casualties have been reported in the offensive. But Israeli ground forces have taken up strategic positions in Gaza border areas, and Palestinian gunmen have been observed preparing for conflict.
In Washington, a White House spokesman said Wednesday Israel has the right to defend itself, and that Hamas should immediately release the kidnapped solider. Spokesman Tony Snow urged Israel to ensure that Palestinian civilians and property are not harmed.
Israeli Prime Minister Ehud Olmert says the offensive is a rescue operation and is not aimed at re-occupying Gaza.
Palestinian officials have denounced the military incursion and say they are trying to secure the soldier's release.
One of the Palestinian militant groups involved in the abduction of the soldier confirmed Tuesday that he is still alive. The group also claims to hold a West Bank Jewish settler, and is threatening to kill him unless Israel stops its Gaza offensive.
Israel has blamed exiled Hamas leader Khaled Mashaal, now living in Syria, for the soldier's kidnapping.
