Which countries are in Nato? Full list as allies agree Ukraine will eventually join

All members of the Nato alliance have agreed that Ukraine will eventually become a member, Nato's secretary general Jens Stoltenberg confirmed on Friday.

A day earlier, during his first visit to the country since war broke out, he had told reporters: "Let me be clear, Ukraine's rightful place is in the Euro-Atlantic family.

"Ukraine's rightful place is in Nato."

More than a year after Russia invaded the Eastern European country, Stoltenberg gave his strongest assurance that Ukraine would be granted membership to Nato - however nothing official has been agreed and no timeline provided, particularly given Nato's Article 5 pledge to defend member countries.

In a joint conference with Stoltenberg on Thursday, Ukraine's president Volodymyr Zelensky said: “We need something more than the kind of relationship we are having now. We will be in their alliance, we believe that is a guarantee of Ukraine’s security and a concrete guarantee.

Read more: Zelensky says now is the time for Ukraine to join Nato as alliance chief visits Kyiv

“But while we await the membership and are not a member, we want to have very specific guarantees of security approved in Vilnius [the Lithuanian capital where July’s NATO summit will be held], if there is an opportunity to do that then we will be ready on our side.”

The move will no doubt increase tensions between Nato and Russia, which has previously listed the prevention of Nato expansion as a reason for military action in Ukraine.

Stoltenberg's comments came shortly after Finlan joined Nato in a move that doubled the alliance's border with Russia.

Previously, Kremlin spokesman Dmitry Peskov had warned that Moscow would be forced to take "countermeasures" and would be "watching closely" what happens in Finland.

He described Helsinki joining Nato as a "violation of our security and our national interests".

The Finnish parliament overwhelmingly approved a proposal to apply for membership to the military alliance in May 2022 following Russia's invasion of Ukraine.

Sweden is also on the brink of joining the alliance after its parliament approved plans on 22 March. Sweden can become a full member country once all of the member countries have ratified its application.

What is Nato?

The North Atlantic Treaty Organization is a political and military alliance of 31 countries.

Nato was set up in 1949 to protect members against the Soviet Union, with 12 nations initially signing up to the North Atlantic Treaty in Washington DC.

These countries were the US, Canada, the UK, Belgium, Denmark, France, Iceland, Italy, Luxembourg, the Netherlands, Norway and Portugal.

What is Article 5?

The collective defence clause of Nato's founding treaty – Article 5 of the Washington Treaty – is a provision that means an attack against one member is considered an attack against all of them.

This is a fundamental part of Nato and why it says it is a defensive alliance.

Nato says military operations are carried out under Article 5 or a United Nations mandate, alone or in cooperation with other countries and international organisations.

If Ukraine joined Nato while the war with Russia was ongoing, this would likely trigger article 5 and therefore brings with it a huge risk of escalating the existing conflict.

Which countries are in Nato, and what date did they join?

1949: Belgium, Canada, Denmark, France, Iceland, Italy, Luxembourg, the Netherlands, Norway, Portugal, the UK, the US.

1952: Greece, Turkey

1955: Germany

1982: Spain

1999: Czech Republic, Hungary, Poland

2004: Bulgaria, Estonia, Latvia, Lithuania, Romania, Slovakia, Slovenia

2009: Albania, Croatia

2017: Montenegro

2020: North Macedonia

2023: Finland