Syrian government forces attacked opponents of President Bashar al-Assad in cities and towns across the country on Tuesday and Arab officials confirmed that regional governments would be ready to arm the resistance if the bloodshed did not cease.

The western city of Homs, heart of the uprising against Assad's 11-year-rule, suffered a bombardment of pro-opposition neighbourhoods for the 11th day running. At least six people were reported killed.

Residents also fled from Rankous, a rural town near the capital Damascus, as it came under government artillery fire.

With Assad seemingly oblivious to international condemnation of his campaign to crush the revolt, Arab countries led by Saudi Arabia pushed for a new resolution at the United Nations supporting a peace plan forged at a meeting in Cairo on Sunday.

But Arab League diplomats said that arming the opposition forces was now officially an option.

A resolution passed at the meeting urged Arabs to provide all kinds of political and material support to the opposition.

This would allow arms transfers, they confirmed to Reuters.

We will back the opposition financially and diplomatically in the beginning but if the killing by the regime continues, civilians must be helped to protect themselves. The resolution gives Arab states all options to protect the Syrian people, an Arab ambassador said.

The threat of military support was meant to add pressure on the Syrian leader and his Russian and Chinese allies but it also risks leading to a Libya-style conflict or sectarian civil war.

I suspect we will see a further militarisation of this conflict, with potentially quite widespread and dangerous consequences, said analyst Salman Shaikh, director of the Brookings Doha Center.

Smuggled guns are already filtering into Syria but it is not clear if Arab or other governments are behind the deliveries. Weapons and Sunni Muslim insurgents are also seeping from Iraq into Syria, Iraqi officials and arms dealers said.

Assad, whose Alawite-minority family has ruled the mainly Sunni Muslim country for 42 years, is trying to stamp out pro-democracy demonstrations and stop insurgent raids across Syria country with what U.N. officials describe as indiscriminate attacks and shoot-to-kill orders.

He dismisses his opponents as terrorists backed by enemy nations in a regional power-play and says he will introduce reforms on his own terms.

While the uprising initially involved rallies by civilians, armed insurrection by the Free Syrian Army, made up largely of army defectors, is increasingly coming into play.

CITIES UNDER THE GUN

Conflict flared anew on Tuesday in Rankous, near the capital Damascus. Activist Ibn Al-Kalmoun, reached by Skype from Beirut, said many residents had fled the town from government shelling.

In Homs, a strategic city on the highway between Damascus and commercial hub Aleppo, the pro-opposition neighbourhood of Baba Amro was struck at dawn by the heaviest shelling in five days, the Syria Observatory for Human Rights said.

Six people were killed, it said, adding to an estimated toll of more than 400 since the assault began on February3

They are hitting the same spots several consecutive times, making venturing out there impossible. The shelling was heavy in the morning and now it is one rocket every 15 minutes or so, activist Hussein Nader said by satellite phone.

Residents are trapped. We have a man who sustained severe burns and is dying and he needs a hospital.

The man was in a truck picking up wounded people in Baba Amro overnight when it was hit by rocket fire, he said.

Mohammad al-Mohammad, a doctor at a makeshift hospital in Baba Amro, appeared in a video with a wounded youth he said was shot by a sniper in his side.

The bullet ended up in the stomach. This is a critical condition that needs transportation to a proper hospital, Mohammad said. We appeal to anyone with conscience to intervene to stop the massacres of Bashar al-Assad and his cohorts.

Another opposition activist, Mohammad al-Homsi, said the humanitarian situation was getting worse, with food and fuel short and prices tripling. Army roadblocks had been set up around opposition districts, Homsi said from the city.

Nader said that people in residential buildings in Baba Amro were sheltering on the ground floors.

Shelling was also reported in the town of Rastan.

Foreign media have had to rely on activists' accounts of the situation because the Syrian government restricts access, although reports from neutral organisations such as the International Committee of the Red Cross and Human Rights Watch confirm the general picture of widespread repression.

DIPLOMATIC THRUST

At the United Nations, diplomats said a draft General Assembly resolution, supporting the Arab League plan and calling for the appointment of a joint U.N.-Arab League envoy on Syria, could be put to a vote on Wednesday or Thursday.

The resolution, seen by Reuters, is similar to a Security Council draft vetoed by Russia and China on February 4 that condemned the Assad government and called on him to step aside.

There are no vetoes in General Assembly votes and its decisions are not legally binding.

An Arab League proposal for a joint Arab-U.N. peacekeeping mission be sent to Syria elicited a guarded response from Western powers, who are wary of becoming bogged down militarily in Syria. It was rejected out of hand by the Assad government.

Russia, Assad's main ally and arms supplier, also showed little enthusiasm, saying it could not support a peacekeeping mission unless both sides stopped the violence first.

U.S. Secretary of State Hillary Clinton said in Washington that the peacekeeper proposal would be tough to get through, given Russian and Chinese support for Damascus.

There are a lot of challenges to be discussed ... and certainly the peacekeeping request is one that will take agreement and consensus, Clinton said.

The Syria conflict, the most prolonged of the revolts in the Arab world which saw the leaders of Tunisia, Egypt and Libya toppled last year, is shaping up to be a geopolitical struggle reminiscent of the Cold War.

Russia wants to retain its foothold in the region and counter U.S. influence. Assad is also allied to Iran, which is at odds with the United States, Europe and Israel.

The Arab drive against Assad is led by Sunni-ruled Gulf states, who also see Shi'ite Iran and its shadowy nuclear programme as a threat.

Analysts say the conflict could spread across the Middle East's ethnic, religious and political fault lines if it is not resolved.

(Reporting Edmund Blair, Yasmine Saleh and Ayamn Samir in Cairo, Erika Solomon in Beirut, Khaled Yacoub Oweis in Amman and Louis Charbonneau at the United Nations; Writing by Angus MacSwan in Beirut; Editing by Mark Heinrich)