DAMASCUS, Feb. 22 (Xinhua) -- Airstrikes continued Thursday on the last rebel enclave near Syria's capital as the United Nations (UN) Security Council considered a resolution demanding a 30-day humanitarian ceasefire across the Mideast country.

Meanwhile, the Syrian government forces urged civilians in the besieged Eastern Ghouta region on the outskirts of Damascus to move to areas under its control, and gave instructions on how to take safe exits in leaflets dropped by helicopters, reported the War Media, the media wing of the Syrian army.

The Security Council held discussions Thursday on the escalation of violence in Eastern Ghouta, but failed to agree on a draft resolution demanding a ceasefire.

The resolution, drafted by Kuwait and Sweden, demanded "a cessation of hostilities throughout Syria for all military operations except those directed at the Islamic State ... al Qaeda and al Nusra Front" for 30 days to allow emergency aid deliveries and medical evacuations.

In response to the Swedish call for a council vote Thursday, Russian Ambassador to the United Nations Vassily Nebenzia said that "the conflict deepens in the Arab country due to a sharp rise in terrorist attacks," and proposed amendments to the resolution text for "it to be realistic."

Reports of civilian deaths and hospital attacks during the latest escalation of violence in Eastern Ghouta have prompted calls for an immediate halt to the fighting.

The Syrian government said the rebels have rained mortar shells down on Damascus while its forces retaliated with intensified airstrikes and shellings. A day earlier, the Syria-based Russian Reconciliation Center said the rebels didn't respond to calls for laying down their weapons and a ceasefire.

Nebenzia on Wednesday asked the 15-member Security Council to meet on Thursday to discuss the situation.

The latest airstrikes in Eastern Ghouta, for the fifth day in a row Thursday on the rebel stronghold of 400,000, was believed to be the fiercest of its kind in the seven-year civil war in Syria.

Heavy shelling and aerial bombardment were reportedly going on over the past 24 hours, killing at least 50 people and wounding at least 200 others, said Mark Lowcock, the UN undersecretary-general for humanitarian affairs and emergency relief coordinator, on Thursday.

Lowcock called on the Security Council to take "urgent and concrete action."

"What we need is a sustained cessation of hostilities, and we need it desperately -- a cessation of violence that will enable the immediate, safe, unimpeded and sustained delivery of humanitarian aid and services, the evacuation of the critically sick and wounded and an alleviation of the suffering of the Syrian people," he told the council.

Ma Zhaoxu, China's permanent representative to the United Nations, reiterated on Thursday China's stance on the Syria issue that political settlement is the only way out, while noting that the pressing task the international community now faces is supporting the Syrian parties in resuming dialogue and negotiation under UN mediation as soon as possible.

"We condemn all acts of violence that target civilians and civilian facilities and hurt innocent lives," Ma said at the council briefing on Syria.