The governing Hamas movement today said Israel's expanded military offensive in Gaza had complicated efforts to resolve a crisis over an abducted soldier and hardened Palestinian positions on the captive's fate.
The group vowed to respond to violence yesterday in which 19 Palestinians and one Israel soldier were killed, saying the Jewish state would "pay the price for every drop of blood".
"The issue of the captured soldier has become more complicated than before," Hamas said in a statement.
"The government of the Occupation is wrong to think the Zionist massacres it is committing against our people will serve its goals of applying pressure to regain the captured soldier."
Israel launched its offensive to force militants to release Corporal Gilad Shalit, who was seized in a cross-border raid from Gaza on June 25, and to also halt rocket fire.
Members of the Hamas armed wing were among those who abducted Shalit. Diplomatic talks led by Egypt have failed to secure his release. Israel has also refused to free Palestinian prisoners in return for Shalit.
Meanwhile, the Israeli military chief said today that Israeli forces have killed nearly 40 Palestinian militants since an offensive was launched in the Gaza Strip last week.