for talks on the sidelines. the leaders of the world s two biggest economies have a lot to discuss not least their ongoing disputes over trade, technology, taiwan and the drug fentanyl. the bbc s james clayton is in san francisco and sent us the latest. apac has started here and it is a huge apac has started here and it is a huge moment apac has started here and it is a huge moment for apac has started here and it is a huge moment for the apac has started here and it is a huge moment for the city apac has started here and it is a huge moment for the city of san francisco. it is summer to be held here since the united nations charter was signed here in 1945. nations charter was signed here in 1916. this is a huge economic summit. you are talking about more than 50% of the worlds trade belongs to the 21 nations who will be attending here this week. talking about 40% of the world s population. it is a big economic conference but by far the biggest ticket item here is the bigge