What are NATO steps if Russia decides to invade Ukraine?

The following are some of the dilemmas about NATO's future steps.

Will I go? NATO in defense of Ukraine?

Not militarily. Ukraine is not a NATO member and the alliance is not obliged by the treaty to protect it. US President Joe Biden has said he will not send American troops or allies to fight Russia in Ukraine.

However, Ukraine is a close partner and it has been promised alliance membership at a NATO summit in 2008.

At the moment, 30 NATO members are working with Ukraine to modernise its armed forces. Canada operates a training programme in Ukraine, while Denmark is also stepping up efforts to bring Ukraine's army to NATO standards. The alliance has also said it will help Ukraine defend against cyber attacks and is providing secure communication equipment for military command.

In Ukraine?

The United States, Britain and the Baltic states are sending weapons to Ukraine, including antitank missiles, small arms and boats. Turkey has sold Ukraine fears that the Ukrainian Army has used against Russia-backed separatists.

Germany, however, opposes sending weapons to Ukraine. Berlin has instead promised a full field hospital and training needed for Ukrainian troops, worth about $6m.

So why is NATO putting them on alert?

The U.S. Department of Defense has put about 8,500 American troops on increased alert. Denmark is sending a frigate to the Baltic Sea and four F-16 fighter aircraft to Lithuania. Spain has sent a miner and a frigate to join NATO's sea forces in the Mediterranean and the Black Sea.

Madrid is also considering sending combat aircraft to Bulgaria, while the Netherlands has offered Bulgaria two F-35 combat aircraft since April.

France could send troops to Romania under NATO command.