General elections in Bosnia and Herzegovina took place over 10 months ago, but the country still hasn't formed a new government.

Members of the country's multi-ethnic presidency on Tuesday again failed in an attempt to break the deadlock at a meeting in Sarajevo.

Here's why forming a government is proving so difficult:

What are the three main ethnic groups?

Bosnia's three-member presidency is formed of Serb, Bosniak and Croat representatives.

Nationalist parties and politicians from these three groups won most votes in the election last October.

Pro-Russian Bosnian Serb leader, Milorad Dodik became the Serb member of the joint presidency, with Sefik Dzaferovic becoming the Bosniak member and Zeljko Komsic, a moderate politician, completing the trio as the Croat member.

Why is it so complicated to form a government?

Bosnia is a country with sharp ethnic divisions and experienced a devastating ethnic war between 1992 and 1995, which saw over 100,000 people lose their lives and left millions homeless.

In order to put an end to the war, the US-brokered a peace deal, installing a complicated network of overarching institutions, including the tripartite presidency, a Council of Ministers — the country's de facto government — as well as multiple assemblies.

For the national government to be formed, politicians from the three groups have to come to a joint decision on the division of ministries and also policies.

Conflicting opinions on relations with NATO

The main sticking point between the three parties, and the reason talks on Tuesday ended without an agreement on forming the new cabinet, is the question of Bosnia moving closer to becoming a member of NATO.

In 2010 it joined NATO's Membership Action Plan (MAP) — a first step in joining the organisation, with NATO last year giving the green light to for Bosnia to advance.

However, the country’s Serbs are Orthodox Christians and staunchly pro-Russian, thus Dodik has always been against joining the alliance, insisting he wants to retain neutrality.

While the Bosniak and Croat members insist on submitting a plan for reforms needed to join NATO, Dodik said he will only go as far as accepting the country' European Union (EU) membership goals.

Disagreement over the Balkan country's future relationship with NATO between the Serbs and the two other groups could both further hamper an eventual government deal and worsen ethnic divisions.

What's next?

An agreement of some kind between the three representatives is critical as the lack of a government is stalling economic evolution in Bosnia, which is still struggling to recover after the bloody war of the 1990s.

What's more, if the country remains deadlocked, it will remain behind other EU hopefuls in the Balkans — a troubling prospect for the country's youth who are leaving in droves each year.

This article was updated on August 22 to say Bosnia's three-member presidency is formed of Serb, Bosniak and Croat representatives.

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