Turkey's Foreign Minister Ahmet Davutoglu lashed out Sunday at the world community's failure to end the bloodshed in Syria, saying that one day a UN chief will apologise for it.

"The international system is failing like it failed in Bosnia for three years, like it failed in Rwanda for many years," Davutoglu told the Munich Security Conference (MSC).

He pointed out that as the UN has apologised over its failure to act on time in Bosnia, "one day another UN secretary general will go to Homs, will go to Yarmuk and will apologise".

What started with 2011 street rallies against President Bashar al-Assad has spiralled into a bloody conflict that has killed over 130,000 people and drawn in regional players and jihadists.

The besieged city of Homs and the Palestinian refugee camp of Yarmuk in south Damascus have been among the worst-hit places for civilians in the conflict.

Assad has received diplomatic support from Russia, which has blocked Western calls for punitive action against the regime in the UN Security Council, along with China.

Davutoglu alluded to the "Arab Spring" and what came after and said "the seasons are according to the sun. The people of Syria now, they don't see any sun, they are in the darkness".

"Who will bring sun to them? Supposedly the UN Security Council, but up to now there is not a single significant step by them," said Davutoglu, adding that Turkey shelters 700,000 refugees.

"Whether China or Russia or US or France or Britain or other member countries, the UN Security Council must take a decision, today," he told a panel at the MSC.