"We don't need these futile firings of rockets and they have to cease so that we can reach a reciprocal truce with the Israelis in the Gaza Strip and the West Bank," Abbas told reporters at a joint press conference with visiting EU foreign policy chief Javier Solana.

Asked if Israel's arrests of the Hamas members were justified, Solana said "No," and also appealed for an end to Israeli air raids in Gaza, rocket fire and Palestinian infighting.

"The temperature has been going up too much and it's time to get the temperature down," he said ahead of a meeting later with Israeli Prime Minister Ehud Olmert in Jerusalem. "No violence is going to resolve any problems."

The 33 officials from the Islamic Resistance Movement (Hamas), including Palestinian education minister Nassereddin al-Shaer, three lawmakers and at least seven mayors, were seized in overnight raids centred on the northern West Bank city of Nablus.

Bloodshed in Gaza over the past week and a half -- a renewed bout of gunbattles between Hamas and Abbas's Fatah and more air raids by Israel -- has sparked widespread international concern and threatened to torpedo efforts to revive the moribund peace talks.

Palestinian information minister Mustafa Barghuti appealed for international intervention after what he said were "kidnappings... a massacre of Palestinian democracy and an aggression against the Palestinian Authority and its institutions."

Israeli Defence Minister Amir Peretz told army radio the move to seize members of the majority partner in the Palestinian unity government was "a message to armed wings of terrorist organisations to stop their rocket fire."

An Israeli military spokesman said the 33 were detained because they "supported the firing of rockets.

"The Hamas terror organisation is currently involved in enhancing the terror infrastructure" in the occupied West Bank and "exploits governmental institutions to encourage and support terrorist activity," the army said.

The arrests came amid continuing Israeli air strikes on Hamas targets in Gaza, which were resumed after a six-month ceasefire in response to a sharp increase in rocket attacks by militants, including those of Hamas.

The Israeli air raids have so far killed 13 civilians and 25 militants, but have failed to halt rocket fire, with nearly 130 crashing inside Israel over the past week and a half, killing one, wounding 16 and sending hundreds fleeing the town of Sderot that has borne the brunt of the barrage.

One civilian wounded in the air raids died on Thursday, medics said.