Syrian activists say more than 100,000 people have been killed since the uprising against President Bashar al-Assad began in March 2011.
The British-based Syrian Observatory for Human Rights announced its latest count Wednesday, saying the figure included 18,000 rebels and about 40,000 pro-Assad fighters.
The United Nations said earlier this month nearly 93,000 people were confirmed dead, but that the actual number is probably much higher.
Members of the Free Syrian Army aim their weapons as they take up a defensive position in Aleppo's Salaheddine district, Syria, June 25, 2013.
A female member of the Ahbab Al-Mustafa Battalion holds a gun as she undergoes military training in Aleppo's Salaheddine district, Syria, June 24, 2013.
This citizen journalism image provided by Aleppo Media Center AMC shows a rebel firing his weapon during heavy clashes with soldiers in Aleppo, Syria, June 24, 2013.
Syrian refugees wait for treatment at an Italian military hospital at the Al Zaatri refugee camp in the Jordanian city of Mafraq, near the Syrian border, June 25, 2013.
A group of Syrian refugees wait for a bus at the Al-Zaatri refugee camp in the Jordanian city of Mafraq, near the Syrian border, June 25, 2013.
Meanwhile, Jordan's King Abdullah warned the fighting in Syria could develop into a regional sectarian conflict. In an interview for the pan-Arab Asharq al-Awsat newspaper, the king said a political solution remains the best way to resolve the crisis.
Also Wednesday, Kuwait's foreign minister addressed concerns about private Kuwaitis financing Sunni extremists in the Syrian conflict.
At a joint news conference with U.S. Secretary of State John Kerry, Sabah Khalid Hamad al-Sabah said fund raising for Syria is tightly restricted to ensure support goes to the "right side" in the conflict.
On Tuesday, Kerry met with Saudi Foreign Minister Prince Saud al-Faisal, who said the world should not allow Iran and the militant group Hezbollah to prop up Mr. Assad's government.
The prince called for an international ban on supplying the Syrian government with weapons, criticizing Russian support for the Assad regime.
Saudi Arabia has been supplying weapons to rebel fighters, while the United States recently said it would send arms in addition to the non-lethal aid it had been providing.