At a time when attention is drawn to the upcoming tripartite summit between US President Donald Trump, his Russian counterpart Vladimir Putin and China's Xi Jinping, the nuclear arsenal stands out as one of the prominent cases related to the global balance of power.
The three countries at the top of the list of countries with the largest nuclear warheads, according to estimates by the International Peace Research Institute in Stockholm.
What is the size of each country's nuclear arsenal? How are nuclear warheads distributed around the world?