Le Pen congratulates Donald Trump

France's far-right leader Marine Le Pen has congratulated Donald Trump as 'the new president of the United States".

France's far-right leader Marine Le Pen has congratulated Donald Trump as the "new president". (AAP)

France's far-right National Front party leader Marine Le Pen has congratulated Donald Trump as he looked set for a shock victory in the US presidential election.

"Congratulations to the new president of the United States Donald Trump and to the free American people!" she said on Twitter.

Opinion polls show Le Pen likely to win the first round of French presidential elections next year but lose in the second round to whoever should be her opponent.