A senior Cambodian official has taken the helm of the Secretariat of Association of Southeast Asian Nations. The new secretary-general called for unity to tackle the region's challenges, such as the situation in Myanmar.

Kao Kim Hourn, a former minister delegate attached to the Prime Minister of Cambodia, took over the role from his predecessor from Brunei.

Kao said, "The next page in ASEAN's important history will be one shaped by new and emerging trends that present both challenges as well as opportunities."

He said he believes there is nothing ASEAN cannot achieve if member nations are united.

The ceremony for the transfer of office was held at ASEAN's headquarters in Jakarta on Monday.

Former secretary general Lim Jock Hoi attended, as well as Indonesian Foreign Minister Retno Marsudi, whose country serves as this year's ASEAN chair.

ASEAN member nations take turns chairing the group, and appointing officials to serve the five-year term of secretary general.

In Myanmar, February will mark two years since the junta took power in a coup. Dialogue between the military and pro-democracy forces is at a stalemate.

Differences have arisen within ASEAN between countries taking a tough stance on Myanmar, such as Indonesia and Malaysia, and those taking a more conciliatory stance, such as Cambodia and Thailand.