BEIRUT — Syrian government forces stepped up their attack against rebel strongholds north of the capital, Damascus on Saturday, while opposition fighters declared their own offensive in the country's largest city Aleppo.

The fighting in Damascus came as the Syrian government announced salary increases for state employees and members of the military, days after the Syrian currency dipped to a record low of 210 pounds to the dollar compared with 47 when the crisis began more than two years ago. The raise also covered pensions.

Both sides intensified operations as an 11-nation group that includes the U.S., dubbed the Friends of Syria, began meeting in Qatari capital of Doha to discuss how to coordinate military aid and other forms of assistance to the rebels seeking to oust Syrian President Bashar Assad.

The donors agreed on Saturday to do more to help the embattled rebels trying to overthrow Assad, U.S. Secretary of State John Kerry said. While he offered no specifics, Kerry said the assistance would help change the balance on the battlefield. Kerry also denounced Assad for inviting Iranian and Hezbollah fighters to fight alongside his troops, saying the Syrian president risked turning the civil war into a regional sectarian conflict.

Activists, meanwhile, reported heavy shelling of many districts north of Damascus, apparently an attempt to cut links between rebel-held districts that have served as launching pads for operations against the capital. Three children, including two from the same family, have been killed in shelling of the outlying district of Qaboun since Friday, according to the Britain-based Syrian Observatory for Human Rights, which relies on an extensive network of activists in Syria.

The Lebanese TV station Al-Mayadeen, which had a reporter embedded with Syrian government forces in the offensive, quoted a military official as saying that the operation aims to cut rebel supply lines, separate one group from another and secure the northern entrances to the capital. The regime's forces have struggled for months to regain control of these suburbs.

The Observatory said the neighborhood was being attacked from several different sides, while the shelling has caused structural damage and started fires. Activists from Qaboun posted on Facebook that government forces had deployed new tanks to reinforce its positions outside the neighborhood, and the bombardment had brought buildings down.

The Observatory said rebels targeted a police academy in the nearby Barzeh area Saturday, pushing back against a government attempt to storm the neighborhood. One rebel was killed in overnight fighting, it said.

State news agency SANA said troops "inflicted heavy losses" among rebels in several suburbs of Damascus.

The uprising against Assad began in March 2011 as peaceful protests but morphed into a civil war as rebels took up arms against a government crackdown. The Syrian regime has gained momentum in recent weeks with the help of Iran and its proxy group Hezbollah. The opposition is hoping the Obama administration's decision to begin supplying them with arms will help swing the tide in their favor.

Rebels say they have already received new weapons from allied countries— but not the U.S. — that they claim will help them to shift the balance of power on the ground. Experts and activists said the new weapons include anti-tank missiles and small quantities of anti-aircraft missiles.

It was not clear if any of the new weapons have made it to the Damascus area. A spokesman for one of the main groups fighting outside of Damascus, the al-Islam brigade, said his group had none of the new weapons. The spokesman, who declined to be named for fear of government reprisals, spoke to The Associated Press on Skype.

He said government forces were shelling Barzeh from Qasioun mountain overlooking Damascus. Syria's main Western-backed opposition group said Thursday that 40,000 civilians in the two northern districts of Damascus are suffering from shortages of food and medical supplies.

Rebels and government also clashed in and around the northern city of Aleppo, where government forces launched an offensive earlier this month. Activists reported clashes in southern and western neighborhoods.

The Observatory also said rebels pounded a military academy in the area, causing a fire in the compound. No casualties were immediately reported. In Rashideen, rebel forces have pushed government forces out from parts of the neighborhood, according to the local Aleppo Media Center network and posts on Facebook.

A statement by a coalition of rebel groups, posted on the Center's page, declared that the fighters are launching a new operation to seize control of the western half of Aleppo.

Also Saturday, Syrian forces fired a dozen shells that landed in a northern Lebanese border town, causing a panic among residents, the Lebanese news agency reported.

SANA said government troops were targeting a group of infiltrators across the border. It gave no further details.

Rockets from Syria fall regularly into towns and villages near the border.

In Damascus, a presidential decree said that the raise for the public sector could reach up to 40 percent depending on the salary of the civil servant. Pensions could rise by up to 25 percent, according to the decree.

It said those who make 10,000 pounds ($54) a month will get a 40 percent raise, while those who make double that amount will get a 20 percent boost. People making 40,000 pounds a month will get a 5 percent raise, it said.