By Louis Charbonneau
UNITED NATIONS, Aug 25 (Reuters) - Humanitarian access in Syria has improved since the U.N. Security Council last month authorized the delivery of emergency aid across the Syrian border without the government's consent, U.N. Secretary-General Ban Ki-moon said in a new report.
But he warned that designated terrorist groups continue to prevent aid workers from accessing some of the estimated 10.8 million people in Syria in urgent need of humanitarian assistance.
"All parties to the conflict continue to deny access to humanitarian assistance in an unjustifiable manner," Ban said. "Hundreds of thousands of people live under siege."
The United Nations Security Council unanimously adopted resolution 2165 last month, which authorized aid access at four border crossings from Turkey, Iraq and Jordan, even though Syria had warned it deemed such deliveries incursions into its territory.
Ban said it was the first time he was able to report improvements since he began submitting monthly updates on aid access earlier this year.
"Access across borders following the adoption of resolution 2165 has resulted in broader reach to areas in Aleppo, Dar'a (Deraa), Rural Damascus, Idleb (Idlib) and Lattakia (Latakia)," he said in the report, obtained by Reuters on Monday.
He said aid access had improved in Aleppo and rural Damascus, adding that "many of these locations had not received assistance since the onset of the conflict."
The Security Council will discuss Ban's report on Thursday.
Ban said medical supplies, including surgical items, reached several rebel-held areas this month.
Aid delivered across Syria's border included food for over 67,000 people, water and sanitation supplies for around 75,000, and medical supplies for almost 110,000 people. Ban said the Syrian government was notified in advance of each cross-border shipment.
Of the overall 10.8 million people in need - roughly half of Syria's population - there are over 6.4 million people who are internally displaced due to the civil war, currently in its fourth year.
Ban said around 4.7 million people reside in hard-to-reach areas, including at least 241,000 people who remain besieged by either government or opposition forces.
There was bad news about militant groups.
"The prolongation of the conflict in Syria has created fertile ground for radical armed groups, including those affiliated with al Qaeda," Ban said.
"Recent events in Iraq and the latest fighting in Arsal, Lebanon, vividly demonstrate the devastating impact of the Syrian conflict on the neighboring countries and beyond," he said. "Countries in the region should find ways to build bridges that promote calm and reconciliation."
He reiterated his calls for an end to arms deliveries to all parties to the conflict.
"The advance of the ISIL into central Syria and reported violations, including extrajudicial killings of civilians and beheadings of those captured is of grave concern," Ban said.
Islamic State fighters, who have seized control of parts of Syria and Iraq, have blocked aid access to northern Al-Hasakah and Aleppo, as well as Kurdish areas, he said. (Reporting by Louis Charbonneau; Editing by Tom Brown)