Hamas said on Friday it had suspended negotiations on the release of a captured Israeli soldier because the Jewish state was not respecting the terms of a truce with the Islamist movement.

"Hamas has suspended indirect negotiations with the enemy over (Corporal Gilad) Shalit because of the non-respect by the enemy of the terms of the truce, notably the opening of crossing points and authorizing the entry of all merchandise" into the Hamas-controlled Gaza Strip, said Osama al-Muzeini, the Islamists' point man on Shalit.

Muzeini was speaking as Israel again sealed off Gaza in retaliation for a rocket attack, itself a violation of the June 19 ceasefire between the two sides.

The truce was supposed to lead to the easing of a crippling blockade Israel imposed after the Islamist movement seized power in Gaza more than a year ago, but the military said the crossings would stay closed until at least Sunday.

Egypt has been mediating with the two sides over the eventual release of Shalit, seized in a June 2006 cross-border raid by militants from Hamas and other Palestinian groups.

A deal would entail freedom for Shalit in exchange for several hundred Palestinians held by Israel. The negotiations have stalled primarily over Israel balking at releasing people with "blood on their hands."