Reality Check takes a look at the facts and figures behind the world's nuclear weapons
Women are marching from Cardiff to Greenham Common as they did in 1981 in protest.
Tough talks lie ahead which may fill the next five years, an ex-Nato deputy secretary general says.
It is their first meeting since Joe Biden became president and the encounter is being closely watched.
By Chris Wood
By Frank Gardner
BBC security correspondent
The SNP Westminster leader says actions this week “expose a tale of two governments, with two very different sets of values".