The USA is worried about China and Russia developing hypersonic missiles. These can travel up to twenty times the speed of sound. A top U.S. military official said China and Russia having hypersonic missiles could be a security problem for the USA. General John Hyten warned that the USA could not stop Russia or China using these missiles against it. He said the USA needed small nuclear weapons to stop anyone attacking the USA. President Donald Trump plans to "get together in the not-too-distant future" with Russian President Vladimir Putin to talk about the arms race.
Russia successfully tested a hypersonic missile this month. China tested its missiles last year. It will soon have its weapons ready for use. President Putin said Russia needed the weapons because of actions other countries have taken against it. He said "unlawful sanctions" have hurt Russia's development. He added: "You have failed to contain Russia." Mr Putin says the missiles can fly anywhere in the world and "strike like a fireball". Tensions increased this week after the UK and USA expelled Russian diplomats because of the poisoning of a Russian spy in England.