European Union foreign policy chiefs on Sunday began a mission to seek a cease-fire in the Gaza Strip but acknowledged they faced a difficult task.

"It is absolutely necessary that violence has to stop," EU External Relations Commissioner Benita Ferrero-Waldner told reporters in Prague before flying to Egypt as part of an EU delegation led by Czech Foreign Minister Karel Schwarzenberg, whose country holds the EU's rotating presidency.

Schwarzenberg acknowledged that it would be very tough for the mission to achieve success.

"It is clear the situation is very bad," Schwarzenberg said at a joint news conference with Ferrero-Waldner.

"We will try to achieve any success we can but we all realize this is very difficult. We will try to open all ways for humanitarian aid to be able to access to Gaza and we will try to discuss what conditions should be set to enable a ceasefire."

Israeli forces began a ground offensive in Gaza on Saturday after eight days of air attacks failed to stop rockets being fired into Israel from the coastal Palestinian territory, ruled by the Islamist movement Hamas.

British Prime Minister Gordon Brown called the Israeli ground invasion "an escalation".

"This is a very dangerous moment. This is a moment where all the hopes of the peace process are falling apart in the action that's being taken. So what we need is an immediate ceasefire," he said in a BBC radio interview.

The EU mission will also include the bloc's foreign policy chief, Javier Solana, and the foreign ministers of France and Sweden, who are due to meet the leaders of Israel, the Palestinian Authority and Jordan during the three-day trip.

French President Nicolas Sarkozy, whose country handed over the EU presidency to the Czech Republic on January 1, planned a separate trip. He will meet the EU mission in Ramallah, the West Bank seat of the Palestinian Authority, on Monday.

Former British Prime Minister Tony Blair, envoy for powers sponsoring Middle East peace talks, was due to meet Israeli Defense Minister Ehud Barak on Sunday.

The Czech EU presidency seemed to suggest there was a division in the EU ranks on Saturday when a spokesman called the Israeli land assault "defensive, not offensive".

But Foreign Minister Schwarzenberg said on Sunday this had been a misunderstanding.

The Czechs said in a statement that even a state's right for self-defense did not justify actions largely affecting civilians, and called for humanitarian aid and ceasefire.

Ferrero-Waldner said the EU would make another 3 million euros available for humanitarian aid.

Asked what the EU delegation could achieve, Solana told BBC radio: "We are going to talk to everybody, with both sides, the Arab countries, the United Nations."

He said there was also the possibility of the EU deploying people on the ground.

"We have deployed already in Rafah in the past. We are ready to go back. And thirdly, help on the humanitarian aspects.

Turkey condemns Israel's ground offensive

Turkey condemned Israel's ground offensive in the Gaza Strip on Sunday and said it would only lead to "more blood and tears."

Turkey's foreign ministry said Israel's launching of a ground operation despite the warnings of the international community and worldwide public outrage was unacceptable, and it urged the United Nations' Security Council to tackle the crisis.

Turkey, starting a two-year term as a member of the UN Security Council, tried last week to broker a truce through visits by Prime Minister Tayyip Erdogan to Arab leaders.

"Seeking a solution through a military path will achieve no result other than opening the way to more blood and tears," a Turkish Foreign Ministry statement said.

"We repeat the call for a lasting ceasefire...and halting Israel's military operation without causing more loss of life and more instability in the region."

Protests against Israel's action took place across Turkey for a third successive day on Sunday. Several hundred thousand people braved chilly conditions to gather in an Istanbul square, according to Reuters television.

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