The United States announced new sanctions Friday against Syria and its supporters, focusing on Hezbollah's support for the regime and a Syrian oil company for violating U.S. sanctions on Iran.
The U.S. State Department sanctioned the refiner Sytrol for selling $36 million of gasoline to Iran in April.
Earlier Friday, the U.S. Treasury Department announced an extension of sanctions against Hezbollah, a Lebanon-based Shiite militant group, for its support of the Syrian government.
Hezbollah, which the United States has designated a terrorist organization supported by Iran, has provided training, advice and extensive logistical support to President Bashar al-Assad's military campaign against an uprising that began in March 2011, the department said.
The agency accused the group of training Syrian government personnel inside Syria, and facilitating the training of Syrian forces by the Quds Force, an elite unit of Iran's Revolutionary Guard Corps.
"Hezbollah's extensive support to the Syrian government's violent suppression of the Syrian people exposes the true nature of this terrorist organization and its destabilizing presence in the region," Under Secretary for Terrorism and Financial Intelligence David S. Cohen said in a statement.
Friday's announcements came as fighting for control of Aleppo continued.
Also Friday, Great Britain announced $7.8 million more aid for the Syrian rebels.
The money is intended not for weapons, but for medical and communication supplies, British Foreign Secretary William Hague said.
"The people of Syria cannot wait indefinitely," he said.
Hague's announcement came as shelling and clashes continued throughout Syria.
Syrian security forces killed at least 180 people, including 75 in Aleppo, said the Local Coordination Committees (LCC) of Syria, a network of opposition activists.
On Thursday, the opposition group said at least 134 people were killed.
Syrian rebels arrested a number of pro-regime journalists while they were covering military operations in al-Tal, a suburb of Damascus, according to the Syrian Observatory for Human Rights.
Syrian state TV reported that a crew from Al-Ikhbariya TV, which is pro-regime, had lost communication with their office and that "armed groups and countries that are supporting them" are to be held responsible.
Residents reported intense shelling Friday in a village in Hama, as well as in two neighborhoods in Homs, the LCC reported.
An activist from the Al Midan neighborhood of Damascus told CNN that tanks were in the streets and smoke was billowing in the capital. Troops, he said, were raiding homes and arresting people.
"The situation is terrible," said the activist, who was not identified because of security reasons.
Witnesses also reported shelling in Aleppo, Syria's largest city, the LCC said.
Syrian armed forces were inflicting "heavy losses" on rebels in the neighborhoods of Al-Ithaa and Saif Al-Dawla, Syrian state TV said Friday.
The Syrian government and rebel groups have been battling for days to control Aleppo, a key front in a conflict that morphed into a civil war after government forces began cracking down on peaceful protesters in March 2011.
The International Committee of the Red Cross said Friday that its first convoy in two weeks had entered the city a day ealier and was delivering humanitarian aid.
"Our priority has been getting them food, clean water, mattresses, things people take for granted," said Rabab Al-Rifaï, head of communication for ICRC Damascus.
"Though the ICRC and the Syrian Arab Red Crescent are doing everything possible to assist civilians affected by the violence, it is up to the parties to the conflict to take every feasible measure to spare the civilian population the effects of the fighting," said Marianne Gasser, the head of the ICRC delegation in Syria.
The Syrian Arab Red Crescent had suspended most of its activities due to the danger, she said. "Still, dozens of volunteers have continued to work under extremely difficult conditions to meet the growing needs of the civilian population."