MANILA - The National Museum has declared the Post Office Building here as an "Important Cultural Property" (ICP) as the Philippine Postal Service marked its 251st founding Anniversary, the Philippine Postal Corporation (PHLPost) said Saturday.

Establishments declared as ICPs are "cultural assets that possess exceptional cultural, artistic and/or historical significance," PHLPost said in a statement.

The postal system in the Philippines started in 1767 in the first Manila Post Office in Escolta.

The neo-classical Post Office building in the heart of Manila was built in 1926 by Filipino architects Juan Arellano and Tomas Mapua, and was refurbished after the second World War.

The Philippine Postal and Philatelic Museum will soon be added in the complex to house a historical archive of stamps that documents 250 years of postal heritage in the country, PHLPost said.