WASHINGTON — Joint reconstruction efforts in Afghanistan between NATO and U.S. forces continue to face myriad challenges as they provide multilateral security sector assistance in the country, according the special inspector general for Afghanistan reconstruction.

John Sopko presented the findings from a report, “Divided Responsibility: Lessons From U.S. Security Sector Assistance Efforts in Afghanistan,” during a speech Thursday at a NATO conference.

“The first challenge is that after 17 years, there is no single person, agency, country or military service that has had sole responsibility for overseeing security sector assistance in Afghanistan,” he said. While the U.S.-NATO commander is largely responsible for the effort, the commander has no direct authority over civilians participating in the mission, he noted, leading to uneven development of the Afghan security force and hindering the standardization of security sector assistance programs in the country.

Furthermore, countries consistently deploy fewer troops than they actually pledge, he said. These “chronic shortfalls” create their own challenges in the mission, he added.

Countries also place caveats on the use of their forces, such as geographic limits, the inspector general said. “When countries were viewed as withholding their full effort, it created the perception of placing a disproportionate burden on others,” he explained.

One study cited in the report found that Afghan leaders prefer working with U.S. advising teams because those teams are not restricted to specific areas.

But Sopko also discussed the benefits of NATO’s involvement in Afghanistan.

Personnel from other nations possess expertise that would not have been available in a solely American mission, he explained. Czech, Lithuanian and Hungarian advisers provide training on Soviet-style aircraft, such as the Mi-35 and Mi-17 helicopters, and Italian, Romanian and Turkish advisers leverage their police training experience, Sopko added.

Coordinating a multilateral approach is also made simpler under a NATO umbrella, he said.