Italian foreign minister Federica Mogherini was chosen Saturday as the EU's next foreign policy chief. Reuters/ Yves Herman

EU leaders elected Polish Prime Minister Donald Tusk as president of the European Council and Italy’s Foreign Minister Federica Mogherini as the head of foreign policy at their meeting in Brussels Saturday.

Tusk, 57, is known for his hard-line stance against Russia, and picked up strong support from both German Chancellor Angela Merkel and U.K. Prime Minister David Cameron despite a heated disagreement between Tusk and Cameron earlier this year over benefits payments and migration policy. The European Council sets the EU’s political agenda, and as president, Tusk will chair all EU summits over the course of his 2 1/2 year term, which begins in December.

Mogherini faced, perhaps, the more difficult road to her new post -- including criticisms that, at age 41, she lacked the experience to become the EU’s foreign policy chief and hasn’t been tough enough on Russia. Italy is one of the biggest consumers of Russian gas.

However, Italian Prime Minister Matteo Renzi lobbied hard on her behalf, and Mogherini has also defended her credentials, as the Financial Times reports.

“I’m a foreign minister of a G7 country,” Mogherini said, according to the FT. “It’s this year [been] 20 years I’ve been involved in European and foreign issues.”

Whereas Tusk holds the distinction of Poland’s longest-serving prime minister (he was first elected in 2007), Mogherini only just this year became the Italian foreign minister -- the youngest person in Italy ever to assume the role, the Guardian reported.

Born in Rome in 1973, Mogherini earned a degree in political science from La Sapienza university, where she wrote her thesis on politics and Islam. During the 1990s she volunteered with the Italian Recreational and Cultural Association, and campaigned against racism and xenophobia.

First elected to parliament in 2008, Mogherini is today considered a center-left politician and a “fresh-faced, vigorous” leader within the Renzi government, the Guardian said. A mother of two, Mogherini is also fluent in English and French.

Soon, she and Tusk, along with the incoming president of EU Commission, Luxembourg's ex-Prime Minister Jean-Claude Juncker, will have to work with one another to chart a course on Russia, as the possibility of further EU sanctions on Moscow looms.

In comments made Saturday, Mogherini emphasized diplomacy with Russia, according to Reuters: "As we think and we work on the level of sanctions, we also have to keep the diplomatic way open ... hoping that the combination, a wise combination, can be effective," she said.