The relations between NATO and Russian have not been this bad since the end of the Cold War.

Following Russia's annexation of Crimea, NATO has stopped practically all cooperation with Russia but preserved diplomatic ties.

NATO believes that an independent and stable Ukraine is key to security in the Euro-Atlantic region. The alliance also wants Russia to withdraw its forces from Crimea and the border with Ukraine and to stop supporting armed pro-Russian insurgents.

NATO members are now debating long-term measures, which could include increasing the presence of troops, weapons and ammunition on Ukraine's eastern border.

The ministers will also address a number of defence-related issues on Tuesday, including plans for the future, capacity development, cyber defence and maritime issues.

The ministerial is to address defence funding cuts, which will expectedly also be on the agenda of the September summit. NATO Secretary General Anders Fogh Rasmussen and the US have been underlining throughout the past years that security does not come cheap.

Since the start of the economic crisis, Slovenia has lagged behind in terms of defence funding. So far, NATO has shown understanding for the country's financial issues but more input is expected as economic recovery starts to set in.