US Secretary of State Marco Rubio has demanded that Panama make "immediate changes" to what he calls the "influence and control" of China over the Panama Canal. The warning follows President Donald Trump's vow to retake the canal and a meeting between Rubio and Jose Raul Mulino, Panama's conservative president, in Panama City on Sunday. On the other hand, Mulino told reporters he did not see a serious threat of US military force to seize the canal, saying he had proposed technical-level talks with the US to address Mr Trump's concerns about Chinese influence.