BEIRUT, Lebanon — Receiving a high-level United Nations delegation on Saturday in Damascus, Syria’s foreign minister blamed international sanctions for his country’s problems and called on the United Nations to help lift the measures, which were imposed to punish the government for its crackdown on pro-democracy protesters that spiraled into armed conflict.
Government forces continued airstrikes and artillery barrages in the suburbs of Damascus, the capital, as a top United Nations official, Valerie Amos, visited the city to investigate the needs of Syrians during a conflict that has killed more than 40,000 people and led more than a half-million to flee the country, with many more displaced inside Syria.
The civil war set off by the brutal crackdown on peaceful protests has devastated many cities and suburbs as the government levels rebellious neighborhoods and some rebels set off bombs.
But Foreign Minister Walid al-Moallem and other officials placed the blame elsewhere, according to Syrian and foreign news reports, saying, “The sanctions imposed by the United States and countries of the European Union on Syria are responsible for the suffering of the Syrian people.”
In the northern city of Aleppo, rebels claimed to have taken another important military installation, the region’s infantry school, though some reports said that fighting continued on Saturday.
There was an outpouring of grief from antigovernment activists and fighters after a commander of a rebel group, the Tawhid, or Unification, Brigade, was reported to have died in the fighting. It was an unusual moment of focus on an individual in an uprising with few widely known leaders or public faces.
The commander, Yousef al-Jader, also known as Abu Furat, had earlier recorded a statement, posted online on Saturday, that resonated with many Syrians.
“I feel very sad whenever I see a dead man, whether from our side or their side,” he said.
Speaking about President Bashar al-Assad, who has resisted calls to step down, he asked: “Why did he have to hold on to his seat? If he had resigned, we would have the best country in the world.”
Opposition members were distraught over the death of Mr. Jader, considered a skilled and respected officer by others in the loose-knit Free Syrian Army.
“A man has left our world, and men are few,” Samar Yazbek, a prizewinning novelist, wrote on Facebook, adding that Mr. Jader’s statement had made her cry. “His quavering and humanitarian voice represented, for me, the lovely and difficult future of Syria,” she wrote. “He barely lighted a star in the sky of our pain!”
The commander was one of many fighters to die in the fighting at the infantry school, which is north of Aleppo, in Muslimiyah.
A Syrian activist in the region, reached by phone, said rebels, who had breached the school’s compound several days ago and had been fighting for it building by building, had lost as many as 25 fighters there on Saturday. “It was a big victory for us, but very costly,” said the activist, Yasser al-Haji.
It is unclear whether the rebels will keep control of the base. In many cases, rebels have quickly taken ammunition from captured bases and then abandoned them, wary of government attacks.
In Jordan, officials who defected from the Syrian government announced that they had formed a new opposition group led by Mr. Assad’s former prime minister, Riyad Farid Hijab, one of the highest-ranking officials to desert during the conflict.
The group, called the National Free Coalition of the Workers of Syrian Government Institutions, aims to keep state structures intact if Mr. Assad’s government falls, Reuters reported.
The group includes Abdu Hussameldin, the former deputy oil minister, and others, who, at a news conference in Amman, expressed support for the Free Syrian Army and the National Coalition of Syrian Revolutionary and Opposition Forces, recently recognized by the United States and others as the legitimate representative of Syrians.
Fighting continued east of Damascus; activists reported airstrikes in Beit Saham, near the Damascus airport. The government claims to have pushed rebels out of some southern suburbs after heavy shelling, and is now focusing attacks in the east in an effort to seal off the capital.
While rebels appeared to make many some gains in a semicircle of suburbs around the capital in recent weeks, those were followed by a fearsome government counterattack, and some analysts have suggested that what began as a victory for the rebels has become, as has happened several times before, a defeat.
The government may have led rebels into a trap, reported the Lebanese newspaper As-Safir, a left-leaning publication that often supports the pro-Assad Lebanese group Hezbollah. Citing informed sources, the newspaper said that the government intentionally withdrew forces from some Damascus suburbs to draw rebels in, stretch their supply lines and later wipe them out.
Syrian state news media reported that Leila Zerrougui, a United Nations special representative, visited camps for families displaced by the fighting and called on all sides to protect children affected by the conflict.