Melania Trump is more popular than her President husband, according to a new poll.

More than half of US voters — 51 per cent — view the First Lady favourably, up 16 points from August last year, according to the survey by Fox News, Mr Trump's favourite TV channel.

Ms Trump had gained support from both Republicans and Democrats, while 28 per cent of voters rated her unfavourably, the poll found.

Meanwhile, President Trump only scored a 47 per cent favourable rating and was seen in an unfavourable light by 51 per cent of voters.

The numbers are an improvement on those reported by other polls in recent months, when Mr Trump's approval ratings were languishing below 40 per cent.

His wife, despite her growing popularity, has yet to match that of her predecessor, Michelle Obama, Fox News said.

At a similar point in her husband's premiership, Ms Obama enjoyed a rating of 73 per cent favourable and 16 per cent unfavourable, the broadcaster said.