The Northern Ireland Fire and Rescue Service (NIFRS) said it wanted to thank firefighters, support staff, partner agencies and the community for their response and support during the fire.
Mr Jennings was the Officer in Charge on the day of the fire and said the effort to save the building would remain with him forever.
"I will remember this incident for the expertise, resilience and dedication of firefighters and staff right across NIFRS as well as the outpouring of kindness, generosity and public – spiritedness," he said.
"This underpinned and helped reinforce our operational response to this incident. As ever the resilience of the people of Belfast was matched by the action and support they offered."
At one point over 100 firefighters and 14 fire appliances, including six specialist appliances, tackled the blaze.
Mr Jennings praised those who worked behind the scenes while the fire raged.
“The size, scope and intensity of this fire provided many challenges and I can vividly recall that iconic image of the clock in Bank Buildings burning and the impact that had on our personnel working so hard to save the building," he said.
“On a number of occasions that afternoon firefighters had to be withdrawn from internal firefighting operations within the building to prevent injury or loss of life due to escalating fire conditions and collapsing structure. Thankfully we were able to re-enter and establish the fire break within the protected staircases.
“Working in extra ordinary and challenging circumstances firefighters protected this area and are to be highly commended for their diligent efforts in preventing the fire spreading allowing the refurbished rear extension of the building and adjacent properties to be saved."
Mr Jennings paid tribute to Primark staff for their actions on the day.
“Primark staff must also be commended for their swift action in evacuating the building prior to the arrival of firefighters. Their actions undoubtedly helped save lives that day enabling the first responding crews to focus on dealing with the developing blaze," he said.
"In large part due to our work in fire prevention and safety, large incidents like the Bank Buildings fire are rare. However, if they do occur, NIFRS is always prepared to respond quickly and effectively.
"Our contingency plans and resilience built into our operational response ensures that as a fire and rescue service we are always ready to respond to any incident across Northern Ireland.”