HAVANA - Cuban President Raul Castro on Thursday visited the embassy of the Democratic People's Republic of Korea (DPRK) and signed the official book of condolence for late DPRK top leader Kim Jong-il, the official NNTV news reported.

Castro, accompanied by Foreign Minister Bruno Rodriguez Parrilla, offered his "deepest condolences" to DPRK ambassador Kwon Sung Chol, on behalf of the Cuban Communist Party, the government and the people.

The DPRK top leader passed away last Saturday at the age of 69 from a "great mental and physical strain" on the train during a field guidance tour, DPRK's official KCNA news agency reported on Monday.

The Cuban authorities on Tuesday declared three days of official mourning for the DPRK leader, when flags are flying at half mast at the public buildings and military facilities.

Cuba and the DPRK established diplomatic relations on August 29, 1960.

The two countries have maintained close cooperative and trade ties in the fields of energy, health, biotechnology, agriculture and education.