Norway’s VG newspaper alerted the Norwegian court to the mistake shortly after the palace posted a copy of the letter apparently sent out to Mrs Kolinda Grabar-Kitarović on Monday.
"The following congratulatory message was passed from H.M. [his majesty] the King to the Croatian President, HE [His excellency] Herr Kolinda Grabar Kitarovic,” the court announced on its website.
Below was a scan of a letter written in English, in which Kitarovic was again referred to as ‘Mr.’
“Through an error, someone has addressed the president as if she were a man and not a woman,” the court's spokesman Sven Gjeruldsen told VG when they pointed out the mistake. “We apologise for that.”
The error was corrected on the website shortly after, VG reported.
The newspaper did not confirm whether the erroneous letter was ever actually sent, either physically or electronically, although the language on the court website suggested it had been.
Grabar-Kitarović, whose name Harald’s letter also omitted to hyphenate, ran as presidential candidate for Croatia’s conservative party HDZ in December, before going on to win a run-off vote against incumbent president Ivo Josipović in January.
She is a former Croatian foreign minister and from 2011 until 2014 served as the Assistant Secretary General for Public Diplomacy at Nato, the first woman to hold such a high position in the alliance.