Leaders of the European Union's 28 member states, who make up the European Council, are haggling over the top five jobs in the bloc.

In filling the leadership roles, the EU treaties dictate that balance must be sought in party affiliation, geography and population size. But national pride, rivalries and pure politics also come into play, making finding a compromise package a painstaking process. 

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Who are the contenders?

Here's a quick guide to the jobs that need to be filled:

European Commission president

What's the job? Head of the executive branch of the EU, leads a team of commissioners equivalent to a national government's cabinet. The Commission sets the policy direction of the bloc, and its president represents the EU in negotiations on the world stage. 

How's it decided? A candidate is proposed by national leaders via the European Council, and must then be approved by a majority in the 751-seat European Parliament.

Who's leaving? Former Luxembourg prime minister Jean-Claude Juncker's term ends on October 31.

European Council president

What's the job? Chairs meetings of the member state leaders, and represents the EU at major world summits and in bilateral negotiations alongside the Commission president.

How's it decided? Elected for a 2.5-year term by national leaders, via qualified majority voting. To be elected via QMV, a candidate must receive the backing of 21 of the 28 member states, and those states must represent at least 65 percent of the EU population.

Who's leaving? Former Polish prime minister Donald Tusk's term ends on November 31.

European Parliament president

What's the job? The chief representative and spokesman for the parliament, chairs debates in the chamber and presents the parliament's position to national leaders at the European Council.

How's it decided? Elected via majority by members of the 751-seat European Parliament for a 2.5-year term.

Who's leaving? Veteran Italian politician Antonio Tajani's term ends in July.

High Representative for Foreign Affairs and Security Policy

What's the job? The European Union's top diplomat is responsible for the EU External Action Service, and serves a similar role to the foreign minister of a national government.

How's it decided? Appointed for a five-year term by national leaders via a qualified vote at the European Council.

Who's leaving? Former Italian foreign minister Federica Mogherini's term ends on October 31

European Central Bank president

What's the job? Runs the European Central Bank, which oversees the euro and monetary policy of the 19-member eurozone. The ECB chief has enormous influence, and becomes a central player in times of economic crisis.

How's it decided? Appointed for an eight-year, nonrenewable term by national leaders via a qualified majority vote at the European Council. 

Who's leaving? Former Italian central bank governor Mario Draghi's term ends on October 31