A recount of the votes cast in Sunday's first round of presidential elections in Romania has been ordered by the country's top court following allegations that social media platform TikTok gave "preferential treatment" to the surprise winner,

Romania's top court on Thursday ordered a recount of votes in the first round of the presidential election and the country's top security body warned Romania was a key target for hostile actions from Russia after a shock result in the ballot.

A top court issued the ruling just days after an ultranationalist outsider unexpectedly won the most votes in the first round of presidential elections held Sunday.