Philippine President Rodrigo Duterte attends a welcome dinner at the ASEAN Summit in Vientiane, Laos September 6, 2016. [Photo/Agencies]

US President Barack Obama cancelled a planned meeting with Philippine President Rodrigo Duterte because the latter referred to him as a "son of a whore".

Duterte's pejorative words may not have been meant personally as the Philippine president habitually uses colorful language and he has apologized through his spokesperson to Obama. However, analysts point out that the cancelled meeting may herald an emerging crack in US-Philippine ties, and that his use of such words may have been a calculated attempt to gain more leverage in his dealings with the US.

Duterte has made a series of changes to his country's ties with the United States since he took office as he has sought to correct his predecessor's excessive pro-US foreign policy that seriously undermined ties with China and other countries.

Compared with countries such as Vietnam and Malaysia which have tried to strike a balance in their relations with the US and China to maximize their interests, Duterte's predecessor Benigno Aquino III tightly bound the Philippines to the US' pivot to the Asia-Pacific strategy, a policy widely believed to have resulted in the Philippines losing opportunities to share the fruits of China's economic growth.

Duterte has adopted a different approach, and he sent former president Fidel Ramos as his special envoy to China on an ice-breaking trip in early August.

Considering the decades-long military alliance between the US and the Philippines and their close political links, Duterte's changed attitude does not mean Manila seeks estrangement from Washington. The Philippines' vitally important strategic position also means the US will not easily abandon such a chess piece on the board of Asia. During Aquino III's presidency, the US was already using the Philippines as a wedge in the ties between China and the other members of the Association of Southeast Asian Nations.

Duterte is likely to employ the same foreign policy adopted by most Southeast Asian nations and seek a better balance in his country's ties with the US and China.

--Beijing News