Doha is increasing its investment in rebuilding Gaza to $400 million, up from $254 million, Gaza's Hamas premier said on Tuesday during a landmark visit by the Qatari emir.

"The emir agreed to increase the Qatari investment from $254 million to $400 million," prime minister Ismail Haniya said during a press conference in Khan Yunis in southern Gaza to mark the emir's visit.

A group of angry Syrians set fire to their tents in protest at "bad living conditions" at the Zaatari desert refugee camp in northern Jordan, a leading charity said on Tuesday.

"A number of Syrian refugees torched 20 tents last night, protesting bad living conditions in Zaatari and demanding the authorities replace tents with caravans," said Zayed Hammad, head of the Ketab and Sunna Society, a charity that helps hundreds of thousands of Syrians in the kingdom.

Warplanes raided a district of the northern city of Aleppo as fighting across Syria kept up unabated on Tuesday, despite hopes of a ceasefire for later this week, a watchdog said.

The latest violence comes three days ahead of the Muslim feast of Eid al-Adha, during which peace envoy Lakhdar Brahimi has proposed a ceasefire.

A narrow majority of Turks is opposed to any intervention by their country in Syria if President Bashar Assad's regime falls, according to a poll published on Tuesday.

Fifty-one percent of people surveyed believe that Turkey, which shares a long border with Syria, must "remain impartial without favoring any side" in the Syrian crisis, according to the Edam Center survey.

President Bashar Assad issued an amnesty for all crimes committed in Syria "up until today," with the notable exception of "terrorist crimes," state television said on Tuesday.

Assad, who has been fighting a 19-month revolt against his regime, "decreed a general amnesty for crimes committed before October 23," except for those carried out by "terrorists" -- the regime's term for rebels.

A car bomb and mortar attacks against predominantly Shiite neighborhoods in north Baghdad killed at least seven people Tuesday, security and medical officials said.

Multiple mortars struck the Chikouk area while a car bomb exploded in Shuala, all minutes apart at around 6:45 am (0345 GMT), an interior ministry official said.

A court in southern Israel on Monday freed from custody three Israeli citizens who accompanied pro-Palestinian activists on a Gaza-bound boat intercepted by the Israeli navy, their lawyer said, while authorities said 10 foreigners were expelled.

Gaby Lasky said that the three Israelis had been placed under house arrest until Tuesday but were not expected to face further proceedings.

The United Nations has made plans to assemble a peacekeeping force for Syria if a ceasefire proposed by a special envoy takes hold, a top U.N. official said Monday.

U.N. peacekeeping chief Herve Ladsous stressed however that planning was very tentative while fighting rages in Syria and would be dependent on the U.N. Security Council overcoming its bitter divisions on the 19-month-old conflict.

Hopes of a truce being implemented in war-torn Syria during this week's Muslim Eid holidays are "slim," the Arab League said on Monday, as rebels and troops engaged in fierce clashes in Damascus and on northern battlefields.

But the United Nations held on to the hope that the two warring sides will observe a truce during the four-day Eid al-Adha holiday which begins on Friday, saying it had plans to assemble a peacekeeping force if a ceasefire takes hold.

Qatar confirmed that its emir will visit the Gaza Strip on Tuesday, on the first such visit by an Arab head of state since the Islamist Hamas seized control of the coastal enclave in 2007.

Sheikh Hamad bin Khalifa al-Thani "will make a brief visit to the Gaza Strip to inaugurate a number of projects funded by Qatar as part of its efforts to rebuilt the Strip," Qatar's official QNA news agency said on Monday.