Which countries are in Nato? Nato - the North Atlantic Treaty Organization - was formed in 1949 by 12 countries, including the US, UK, Canada and France. It currently has 31 members across Europe and North America. They agree to help one another if they are attacked.

The organisation's original goal was to block Soviet expansion in Europe after World War Two. After the Soviet Union's collapse in 1991, many Eastern European countries joined Nato: Albania, Bulgaria, Hungary, Poland, the Czech Republic, Slovakia, Romania, Lithuania, Latvia and Estonia. Russia has strongly opposed Ukraine's request to become a member, fearing it would bring Nato forces too close to its own territory. However, Finland - which has a 1,340km (832 mile) land border with Russia - became a member in April 2023.

Why does Sweden want to join Nato, and why has Turkey now agreed?

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