Manila - President Benigno Aquino III said on Wednesday his country will lease five aircraft from Japan to help the Philippine navy patrol Manila's territory in the disputed South China Sea.The Asian allies, which have separate territorial conflicts with Beijing, have been deepening their security ties. They signed an agreement last month to allow Japan to supply defence equipment and technology to the Philippines, Tokyo's first such pact with any Southeast Asian country.Aquino said without elaborating that the TC-90 training planes from Japan would be used to help patrol the Philippine territory in the South China Sea. Tokyo and Manila have expressed alarm over China's aggressive assertion of its territorial claims, including its massive construction of islands in the disputed Spratly archipelago.Aquino spoke at a ceremony where the new Philippine Air Force chief, Lieutenant General Edgar Fallorina, assumed his post. Aquino, whose six-year term ends in June, outlined the progress in efforts to modernize his country's underfunded military, one of Asia's most ill-equipped."Were they not saying that our air force before was 'all air and no force?'" he asked.Aquino cited how two FA-50 fighter jets escorted his commercial plane as it entered Philippine airspace as he flew back home from a recent US trip. The FA-50s from South Korea were the country's first fighter jets in a decade since it retired its F5 jets in 2005.In addition to leasing the TC-90 training planes, the Philippines will also acquire a dozen military aircraft this year and in 2017 from other countries, including two more of a dozen FA-50 fighter jets and two C-130 cargo planes, he said.Aquino said the government has spent more than 58 billion pesos ($1.2bn) from 2010, when his term started, to February this year to modernize the country's ill-equipped armed forces.The Philippines has turned to the United States and other allies like Japan as it scrambled to strengthen its military amid escalating territorial disputes with China.