China accused the US of being untruthful and unlawful regarding claims that five Chinese vessels harassed an American surveillance ship in international waters near Hainan island, Reuters reported. Chinese Foreign Ministry spokesman Ma Zhaoxu dismissed the US account of the incident as "gravely in contravention of the facts." Declining to go into further detail on what actually happened, Ma said the USNS Impeccable had violated international sea convention as well as Chinese laws relating to its exclusive economic zones and marine research in its waters. The timing of the incident is unfortunate, coming as Chinese Foreign Minister Yang Jiechi arrived in the US to discuss a meeting between President Hu Jintao and his US counterpart Barack Obama at the G20 summit in London next week. Analysts played down the long-term significance of the spat, saying it was overshadowed by the global challenges the two nations face.