Qatar's leader, a key supporter cheap burberry 2012 of the league, said a positive outcome for the mission was unlikely.
"I could not see up until now a successful mission, frankly speaking," said Prime Minister Sheikh Hamad bin Jassim al-Thani.
The New York-based Human Rights Watch group urged the league to assess whether its mission should continue.
The group said the league's presence had done nothing to force the Syrian government to honour a peace deal it had agreed.
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More than 5,000 civilians have been killed, says the UN
More than 400 killed since start of Arab League mission on 26 December
UN denied access to Syria
Information gathered from NGOs, sources in Syria and Syrians who have fled
Vast majority of casualties were unarmed, but the figure may include armed defectors
Tally does not include serving members of the security forces
Source: UN's OHCHR
"The time has come for the Arab League to call out the Syrian government on its failure to abide by the agreement," said HRW's Anna Neistat.
"Allowing the mission to continue without effective and clear efforts to protect the civilians will only lead to more deaths."
Opposition groups say 24 people died around the country on Wednesday.
A French TV reporter was among those killed - the first Western journalist to die in the unrest.
Gilles Jacquier, who worked for the France 2 channel, was killed in an attack in the city of Homs during a government-authorised trip.
More than 5,000 people have been killed since the unrest began last March, the UN says.
The government of President Bashar al-Assad says says 2,000 security personnel have died combating "armed gangs and terrorists".
It is impossible to verify the claims cheap burberry men as access for foreign journalists is severely restricted.
The league said it was postponing sending new observers because of the attack on its mission in Latakia, western Syria, on Monday.
The league blamed protesters for the attack, but also stressed that the authorities should have protected the team.
The work of the mission has already been hampered following the resignation of one of its observers, Anwar Malek.
In an interview with al-Jazeera broadcast on Tuesday evening, Mr Malek said that by allowing in observers the Syrian government had "gained a lot of time to help it implement its plan" to end the unrest.
"What I saw was a humanitarian disaster. The regime is not just committing one war crime, but a series of crimes against its people," he said.
"The snipers are everywhere shooting at civilians. People are being kidnapped. Prisoners are being tortured and none were released."
Mr Malek said he had resigned because of what he had seen, and asserted that the observer mission had fallen apart.
"The mission was a farce and the observers have been fooled," he added. "The regime orchestrated it and fabricated most of what we saw to stop the Arab League from taking action against the regime."
Mr Malek's name was on a list of the observers who were sent to Syria in late December, according to the Associated Press new agency.
He was identified as a Tunisian who works for the Paris-based Arab Committee for Human Rights (ACHR), although al-Jazeera said he was an Algerian.
Meanwhile, another league observer threatened to quit the mission within 24 hours because its work was ineffectual, Reuters reports.
The observer - who declined to give
burberry bags his name - said: "The mission is unclear. It does not serve the citizens. It does not serve anything".