Syrian opposition chief Ahmed Jarba called Saturday for backers of the rebellion to provide it with the "means to fight" the regime, as the conflict entered its fourth year.

In a speech delivered in Istanbul and articles published in the French and US media, Jarba renewed a call for weapons as the rebels take on both President Bashar al-Assad's regime and jihadists.

"Our fighters are not only facing regime forces and their allied gangs," he said in the speech.

"They are also facing extremist gangs and are cleaning our house of terrorist mercenaries, particularly the Islamic State of Iraq and the Levant (ISIL) and others, who sneak up behind the revolutionaries to stab them in the back in the service of the regime."

He said the opposition had agreed to attend peace talks in Geneva earlier this year, but was still waiting for its backers to deliver weapons they pledged before and during the talks.

"We renew our request to the friends of the Syrian people to immediately keep their promises that were made before and during Geneva to do with qualitative weapons," he said.

"We remind them that the time they are trying to buy today will tomorrow be a sword on the neck of the region and peace and security in the world."

He said the rebels were fighting "mercenaries" from the Lebanese Shiite group Hezbollah, as well as Iraqi and Iranian Shiite fighters.

Hezbollah has acknowledged sending fighters to bolster Assad's troops against the uprising.

In an article attributed to Jarba on the website of French newspaper Le Monde, he said Assad had "failed to crush the revolution" and "would never succeed".

But he also urged the international community to finally provide the military backing to oust the regime.

"The time has come for the free world to help the Syrians to escape their isolation. They should provide the means to fight Bashar al-Assad, and the jihadists that he has done so much to attract."

An English-language version of the article released the previous day made no direct request for military support, a possible reflection of France's greater willingness to engage in military operations in recent years.

France has intervened in Mali and Central African Republic in the past year, and supported direct strikes in Syria last summer following reports that Assad had used chemical weapons.

"Even if the international community (doesn't) have a moral obligation to help the Syrian people, it must act to contain the catastrophe now seeping across every one of Syria's borders, if only for its own interests," the English version concludes.

Turkey threatens retaliation if historic Syria tomb attacked
Ankara (AFP) March 14, 2014 - Turkey warned on Friday that it would retaliate "in kind" if a historic memorial that it controls inside war-torn Syria comes under attack.

"Any kind of attack, be it from the regime or radical groups ... will face retaliation in kind and Turkey will take any measures to defend its homeland without any hesitation," Foreign Minister Ahmet Davutoglu said.

The Tomb of Suleyman Shah, the grandfather of Ottoman Empire founder Osman, is located in the province of Aleppo, the scene of major clashes between the Syrian government and several rebel groups.

The tomb sits 25 kilometres (15 miles) from the Turkey-Syria border and remains Turkish territory under a 1921 treaty signed between Turkey and France, which was then the colonial power in Syria.

That agreement was renewed after Syria gained independence in 1936.

A Turkish flag flies over the tomb and a small garrison of around 25 troops is permanently stationed there, according to Turkish media reports. It is Turkey's only overseas territory.

The foreign minister's comments came after local media reported that Turkey had put its military on alert against any threat from jihadist groups to the tomb.

Davutoglu said the extremist Islamic State of Iraq and Syria (ISIS) was trying to take control of the area around the tomb, but said for now there was no direct threat to the Turkish enclave.

Nonetheless, the soldiers stationed at the tomb have been ordered to strike back against any attack, according to the Hurriyet newspaper.

"Turkey has the right to take any kind of measures for its security and stability," Davutoglu said.

"We hope that the security of our troops and territory there will not be infringed, but we are fully prepared for every possibility."

Turkey is a staunch opponent of the Syrian regime of President Bashar al-Assad and hosts more than 750,000 refugees, many of them in camps along the border.

But Ankara is worried about extremist groups fighting in Syria which it says threaten its own security, and it has occasionally closed its border crossings out of security concerns at times of intense clashes.

"The risk has been there since the Syrian crisis first erupted," an official told AFP on condition of anonymity.

Ban wants Russia, Iran to push Syria over peace talks
United Nations, United States (AFP) March 14, 2014 - UN Secretary General Ban Ki-moon on Friday said Russia and Iran should pressure their ally in Damascus to re-start peace talks aimed at ending the three-year Syrian civil war.

The UN-led peace talks, dubbed Geneva II, broke down on February 15 when a second round ended and no new date was set for them to reconvene.

UN and Arab League envoy Lakhdar Brahimi said earlier this week the Syrian government was engaged in "delaying tactics" aimed at slowing the resumption of the talks to end the conflict that has left more than 146,000 people dead and driven millions from their homes.

"Anyone who has influence, the Russian government or the Iranian government, may impress upon the Syrian authorities so that they will come with a more constructive attitude to the Geneva conference," Ban told reporters.

Ban was speaking after an informal meeting of the UN General Assembly attended by Brahimi, who is to head on Sunday to Tehran.

"Iran is one of the important regional countries who can play an important role, including impressing upon the Syrian authorities to come to the Geneva conference in a more constructive way," Ban said.

Asked about the upcoming presidential vote in Syria -- planned for this summer -- Ban repeated Brahimi's comments from Wednesday.

If President "Assad becomes a candidate, then it is very difficult to move ahead the Geneva peace process," because one of the goals of the talks is to create a transitional government in Syria, Ban said.

Bashar al-Assad has not announced his candidacy but is widely expected to seek another seven-year term.