"Poor relations with China might push Southeast Asian nations into joining the US-dominated Trans-Pacific Partnership trade deal that does not include Beijing, and also make them less enthusiastic towards the Regional Comprehensive Economic Partnership that Beijing is supporting."
The diplomatic manoeuvrings by the top two Chinese leaders over the past two weeks in Southeast Asian nations saw Beijing reshaping its priorities towards its mostly wary neighbours.
In the absence of US President Barack Obama, who chose to stay at home to deal with the government's shutdown crisis, President Xi Jinping and Premier Li Keqiang came under particularly close scrutiny in their separate trips to five Southeast Asian nations.
One of Beijing's achievements was the agreement reached after talks between Li and his Vietnamese counterpart, Nguyen Tan Dung, on Sunday to form a working group to jointly explore the disputed waters in the South China Sea.
There were no concrete details about how such a project would proceed, but observers said securing the agreement with Vietnam - one of the two strongest claimants to the disputed areas, along with the Philippines - indicated that Beijing's recent tactics had paid off.