Efforts to evacuate civilians and wounded from the battered Syrian city of Homs failed again when a rescue team could not enter affected areas, the International Committee of the Red Cross (ICRC) has said.
Beatrice Megevand-Roggo, head of ICRC operations for the Near and Middle East, said in a statement that there had been an agreement from Syrian authorities and the opposition for the ICRC team to carry out an evacuation.
But "on the spot, however, agreed-upon conditions were not met and the staff were unable to proceed", she said.
The U.N. refugee agency doubled its forecast for the number of refugees who will flee Syria this year to 185,000 and said it would need more than twice as much money as previously thought, the U.N. coordinator for Syrian refugees Panos Moumtzis said.
Refugee numbers have doubled to 96,000 since March, forcing the United Nations to revise its forecast.
U.N. humanitarian agencies and their partner organisations now say they need $193 million (£124 million pounds) to help the refugees, more than twice the $84.1 million (£54.2 million pounds) they appealed for in March
Fire crews can be seen spraying water on a number of cars in the car park of the Palace of Justice in central Damascus in this footage from Syrian state TV.
It is not yet known whether there were any casualties. Syria's government has described the blast as a "terrorist explosion".
Thick billows of smoke are clearly visible over the Palace of Justice in Damascus - Syria's highest court.
The building appeared intact as firefighters doused cars that were on fire and ambulances arrived at the scene.
Witnesses have told Reuters that at least 20 cars were burned but it is now known whether there are any casualties.
The car park is used by lawyers and judges working at the Palace of Justice.
Amateur video posted on YouTube today purports to show smoke rising from the Palace of Justice in Damascus.
ITV News cannot independently verify the footage.
The video is entitled 'Damascus smoke near the Palace of Justice 28 62 012'.
Reuters witnesses report a loud explosion heard in central Damascus, with smoke seen rising from near the palace of justice.
Syrian state TV is reporting a "terrorist explosion" in the palace's car park.
A Turkish military convoy including anti-aircraft missiles left a base near the Syrian border today and headed for a Turkish province housing a large camp for Syrian refugees, local agencies said.
Video from the DHA agency showed the convoy, of about 12 trucks and transporters, filing through the gates of the base past the hanging Turkish red flag emblazoned with white crescent moon and star.
The Dogan agency said the convoy, from the 5th Mechanised Armoured Brigade, headed for Kilis province, site of a large container refugee camp. Traffic was closed on some roads to allow the convoy through.
Syrian opposition groups say they will not accept a political transition plan proposed by international envoy Kofi Annan unless it explicitly required President Bashar al-Assad to step down ahead of the formation of a unity government.
According to diplomatic sources at the United Nations, Annan's proposal, aimed at ending the 16-month conflict in Syria, does not stipulate Assad's resignation, although it does say the unity government could not include figures who jeopardise stability.
Samir Nashar, an executive member of the international Syrian National Council, said:
The proposal is still murky to us but I can tell you that if it does not clearly state that Assad must step down, it will be unacceptable to us.
Turkey's Prime Minister Erdogan said any military element moving towards the Turkish border and deemed threatening would be declared a military target.
The size and power of air defence weapons in the convoy suggested Turkey was preparing for any possible approach by Syrian helicopters or warplanes.
State-run Anatolia news agency said armoured military vehicles were being transported to military installations in Sanliurfa, in the middle of Turkey's border with Syria and Hatay, a panhandle province that juts down into Syria.
A convoy of about 30 military vehicles, including trucks loaded with missile batteries, has arrived in Turkey's coastal town of Iskenderun and deployed near the the Syrian border 50 km (30 miles) away, Turkish agencies said.
Turkish Prime Minister Tayyip Erdogan announced he would take precautions after a Turkish jet was shot down by Syrian forces last Friday.
A Turkish official said he did not know how many troops or vehicles were being moved but said they were being stationed in the Yayladagi, Altinozu and Reyhanli border areas of Turkey's southern Hatay province. He said anti-aircraft guns were being stationed along the border.