BRUSSELS (AP) — European Union leaders picked Italy's top diplomat to become the 28-nation bloc's new foreign policy chief for the next five years.

EU summit chairman Herman Van Rompuy said Saturday in a Twitter message leaders chose Federica Mogherini to succeed incumbent Catherine Ashton in November.

The decision comes as the crisis at the EU's eastern border pitting Ukraine against Russia poses one of the biggest foreign policy challenges for the bloc in decades.

Mogherini "will be the new face of the European Union in our day-today dealings with our partners in the world," outgoing European Council President Herman Van Rompuy said.

Mogherini, a 41-year-old center-left politician, has been Italy's foreign minister only since February, drawing criticism that she lacks experience. A first attempt to secure Mogherini's nomination in June failed amid resistance from eastern European leaders.

The highly visible job as EU foreign policy chief entails flying across the world and hobnobbing with the great and powerful to deal with anything from the fighting in eastern Ukraine to the crises in the Middle East. However, the EU's top diplomat often has had little leeway because the bloc's member nations jealously guarded foreign policy as a national matter, leaving the foreign policy chief the role to hammer out compromise positions.

Mogherini said she will work relentlessly to promote European projects on the international stage, while fighting off crises or seeds of discord that could undermine the bloc's success.

"We are a dream come true, having to be careful that the dream doesn't turn into a nightmare," she said.

The EU leaders also elected Polish Prime Minister Donald Tusk to succeed European Council President Herman Van Rompuy in December as EU summit chairman and behind-the-scenes broker of compromises among national leaders.

The 57-year-old Tusk, a historian and talented speaker, has led Poland's center-right coalition government since 2007, overseeing continuous economic growth.

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Frances D'Emilio in Rome and Monika Scislowska in Warsaw contributed reporting.

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