Austria's new coalition government, headed by Kurz, the leader of the conservative People's Party (OVP) , was sworn in on Monday, amid protests concerning its right-wing leanings.

Coalition partner, the far-right Freedom Party (FPO), has seen a return to power, following protracted negotiations with the OVP after the Oct. 15 election. Party leader Heinz-Christian Strache is new vice-chancellor.

Tusk on Monday sent a letter of congratulation to Kurz, saying, "I trust that the new government will continue to play a constructive and pro-European role in the EU."

Austria is set to take over the EU's rotating presidency in the second half of 2018.