DAMASCUS  - Fighting for control of a key army base in Aleppo raged on Saturday, as Russia tried to revive a divisive accord on ending the bloodshed that calls for a government of unity in Syria.

As Lakhdar Brahimi prepared for his first visit to Damascus as international envoy on Syria, EU foreign ministers meeting in Cyprus upped the pressure, saying they agreed on the need to beef up sanctions on the Syrian regime. On the ground, the army claimed a victory against rebels in the northern city of Aleppo, ousting them from the Hanano army base backed by tanks and helicopters in a 20-hour battle, military sources and witnesses said. “There are a lot of victims on both sides,” one witness told AFP.

A military official said soldiers destroyed six armoured vehicles the rebels were using to transport arms seized from the barracks - a compound that serves mainly as a weapons depot and recruitment centre. Rebel fighters on Friday claimed to have captured parts of the barracks. “The rebels had thrown themselves whole-heartedly into this offensive because they desperately need weapons,” an army official said.

Badly outgunned members of the Free Syrian Army (FSA) took part in the offensive, a rebel commander who identified himself as Abu Omar said on Friday.

The goal was to liberate Hanano, cut off strategic supply lines and stop the shelling that has caused high civilian casualties in Aleppo. FSA media coordinator Abdullah Yasser said the assault aimed to take one of three main positions the army uses to shell rebel forces concentrated in the city’s east.

“Hanano is one of the main places from which they are shooting, so taking it over could be a turning point for us,” he told AFP. On Friday alone at least 18 soldiers and four rebels were killed in the battle for the base, the Britain-based Syrian Observatory for Human Rights said. The rebels also assaulted Aleppo’s Midan district on Saturday by breaking into the Saint Vartan religious complex between the central district and a rebel stronghold, a military source and local residents said.

The rebels tried to take Midan “but were met with fierce resistance by the security forces of the air force, who are in charge of the area,” the source added.

Aleppo was also suffering from severe drinking water shortages after a main pipeline was destroyed in a northern district of the city, the Britain-based Syrian Observatory for Human Rights said.

“A main water line was destroyed near the water department in Bustan al-Basha. This is very important because it provides drinking water to the whole city,” Observatory director Rami Abdel Rahman told AFP by phone. A number of people have found refuge at Saint Vartan amid the fighting which has engulfed Aleppo since July 20. The Observatory also reported shelling in Damascus, in the southern province of Daraa, and clashes around a military airport in Albu Kamal in the east.

At least 14 people - five civilians and nine rebels - were killed nationwide on Saturday, the Observatory reported, following a bloody day in which 136 people died, the majority civilians. On the political front, Russia said it would ask the UN Security Council to endorse a plan to end the violence in Syria, but the United States insisted any resolution had to have teeth.

Moscow has been the main diplomatic and military supporter of Syria’s embattled President Bashar al-Assad and has angered Western nations by vetoing, along with China, three attempts at the Security Council to exert more pressure.

“There is a plan to hold a special meeting of the UN Security Council with the participation of ministers on the Syrian issue,” Foreign Minister Sergei Lavrov said after talks with US Secretary of State Hillary Clinton in Vladivostok.

“We stressed in a meeting with the US Secretary of State that Russia will push for the Security Council’s approval of the Geneva communique.”

Clinton said she was open to another attempt at the Security Council based on the Geneva plan, but insisted on a resolution to carry consequences if Assad did not comply, a senior US official said.

She told Lavrov that “in the context of the escalating violence, we have got to do more, if we can, in the Security Council to send a strong message,” the official quoted her as saying.

On June 30, world powers agreed on a plan calling for all sides in Syria to implement a ceasefire and then form a transitional government and review the constitution.

But the plan did not make an explicit call for Assad to quit - a demand championed by the United States, Britain, France and Arab states including Saudi Arabia and Qatar who have also been clamouring for tougher sanctions on Syria.

Cypriot Foreign Minister Erato Kozakou-Marcoullis said there was “consensus” in informal talks in Cyprus on Saturday among EU foreign ministers on increasing sanctions against Syria.

Spain’s Foreign Minister Jose Manuel Garcia Margallo said “there is a general feeling that more pressure must be placed on the regime in order to end the violence and enable the distribution of humanitarian aid throughout the country.”

Brahimi, who heads to Cairo for talks with Arab League leaders on Sunday, has said it is up to the Syrians to decide their future, echoing the position of his predecessor Kofi Annan.

His spokesman Ahmad Fawzi said the peace envoy is working on “the final details of a plan to visit Damascus.”

UN diplomats say Brahimi wants guarantees that he will get a proper meeting with Assad before going. The UN says about 20,000 people have died in the conflict which erupted in mid-March 2011. The Observatory says more than 26,000 have been killed - the vast majority civilians.