BELGRADE, Serbia -- Serbia's first openly gay and female prime minister is set to take office in the staunchly conservative country next week after the ruling populists mustered majority support for her in parliament.

Officials said on Friday that the assembly will convene on Saturday to start the proceedings for the election of Ana Brnabic and her government. The vote is likely next week.

Serbian President Aleksandar Vucic proposed the U.S. and U.K.-educated business and marketing expert Brnabic for the post. Her election was thrown into doubt amid reports that hardliners in the ruling coalition had refused support because of her sexual orientation.

Vucic, who switched from premier to president in April, is hosting a lavish formal inauguration ceremony on Friday. Top regional leaders and representatives of foreign governments, including the U.S. and Russia, are attending.

Serbian media have reported that more than 3,000 guests have been invited. The New Belgrade zone where the ceremony is being held will be closed to traffic.

Most of Serbia's opposition politicians will boycott the ceremony and hold a protest in the Belgrade city centre instead. They have accused Vucic of irregularities during the April vote and an autocratic rule in Serbia.

Analysts say Brnabic's nomination is Vucic's tactic to please the West after his recent apparent shift toward Russia. He has formally proclaimed European Union membership a "strategic goal."

Brnabic has said that she "can't wait" to assume the post and start working. She has said her primary goal will be Serbia's economic recovery and modernization.

Vucic is a former extreme nationalist who now says he wants Serbia to reform according to EU standards.

In a meeting Friday with Russia's Deputy Prime Minister Dmitry Rogozin, who came for the inauguration ceremony, Vucic pledged Serbia will not join Western sanctions against Moscow over Ukraine, despite EU suggestions that Serbia must align its foreign policies if it wants to join the bloc.

Serbia's previous, pro-Russian President Tomislav Nikolic also met Rogozin, outlining the country's foreign policy priorities.

"I am no longer president and I can now tell you freely," Nikolic told Rogozin. "We have defined our priorities a long time ago, and that is friendship with Russia while respecting other nations."