Perhaps it was nerves before being serenaded by crossdressing Eurovision singer Conchita Wurst, but UN chief Ban Ki-moon fell into the trap of confusing Austria with Australia during a visit to Vienna.

“I thank in particular (Austrian) President (Heinz) Fischer and the government of Australia,” Ban told reporters at a UN conference of developing landlocked countries hosted by the Austrian capital.

He later corrected himself and apologised in the news conference, saying: “There are no kangaroos in Austria. Sometimes this happens, I hope you understand.”

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Later, Wurst raised the roof for Ban and several hundred UN staff, belting out Cher’s Believe and Rise Like a Phoenix, the song the bearded drag queen sang to win the Eurovision Song Contest earlier this year.

Wurst has used her Eurovision fame to promote a message of tolerance, with performances in front of the European Parliament and at LGBT (lesbian, gay, bisexual and transgender) events around Europe.

Ban paid tribute to her efforts, saying: “I will continue to fight against transphobia and homophobia. I will stand strong for equality. I hope more of you join our global Free and Equal campaign.”

This week’s UN conference of landlocked developing countries brings together 32 nations with a combined population of 450 million people looking at improving transportation networks and access to markets.

Among those present was Robert Mugabe, the 90-year-old president of Zimbabwe, and Bolivian President Evo Morales. Neither attended Wurst’s performance.