Australian experts cautiously optimistic over Xi-Obama summit(3)

However, Dupont said the value of a personal relationship could be overstated.

"Liking each other can only go so far," he said.

"I think Xi and Obama will come to understand each other a little better but there are serious and real differences in national perspectives and they both have very powerful national constituencies that limit what they can say and do.

"Hopefully there is a level of personal trust that could be valuable but how much that will lead to change in policy outcomes is unclear."

Dupont told Xinhua that while having a good relationship with intra-governmental counterparts certainly helps, it's "how both countries respond to the other's complaints and how far they can push the relationship despite opposition from conservatives at home."

"There is rule of scope for the development of a personal relationship but I wouldn't overplay the significance - because at the end of the day, even if it does occur, both countries must make hard-nosed calculations of national interest," he said.

Much has been made of President Xi, who took office in March, and his symbolic ascension as an inter-generational leadership.

Xi boasts a broader knowledge and so far has displayed an obvious ease with the strictures of the 24 hour news cycle and the demands of public and political protocols.

Obama is perhaps under more domestic pressure than his counterpart, according to Reilly, who says that cyber security will top the agenda for Obama who has been rattled by criticism and pressure "in that regard for not being forthright enough."