Yemen's rival sides have agreed to exchange hundreds of prisoners in a move aimed at supporting the United Nations-sponsored peace talks in Switzerland, despite both sides accusing each other of breaching a ceasefire.

A seven-day truce, timed to coincide with the peace talks, began at midday on Tuesday to halt fighting in nine months of war between Houthi rebels and Saudi-backed resistance fighters loyal to President Abd-Rabbu Mansour Hadi.

Al Jazeera's Zeina Khodr, reporting from the talks venue near Biel in Switzerland, said the prisoner swap agreement on Wednesday was "undoubtedly a positive development" in the war.

Abdel-Hakim al-Hasani, a senior southern leader, said 360 members of the Houthi movement held in Aden would be exchanged for 265 southern civilians and fighters on Wednesday, following tribal mediation.

An official from the Houthi-run prisons authority in the capital Sanaa said southern prisoners boarded buses on their way to the exchange venue in central Yemen.

Witnesses in Aden said they saw buses guarded by local fighters travelling through the city, apparently heading to the exchange venue, the Reuters news agency reported.

The Saudi-led coalition's spokesman, Brigadier General Ahmed al-Asseri, said the alliance was committed to the ceasefire but was ready to respond to any violation by the Houthis, according to the Saudi al-Riyadh daily.

PHOTO CAPTION

Police stand outside the Olympia house were peace talks on Yemen are being held in the village of Magglingen, in Switzerland, Dec. 15, 2015.

Al-Jazeera