China’s Foreign Ministry has called on an American diplomat to protest State Department accusations that Beijing is hindering diplomatic efforts in the South China Sea. It’s just the latest controversy in the countries' already tense relationship.

­The ministry said on its website that Assistant Foreign Minister Zhang Kunsheng had summoned the US Embassy's Deputy Chief of Mission Robert Wang to present "strong dissatisfaction and firm opposition" to the statement from Washington.

On Friday, the State Department said that Beijing’s establishment of a military garrison in the area runs against "collaborative diplomatic efforts to resolve differences and risk further escalating tensions in the region,” according to Reuters.