US President Donald Trump's approval rating has dropped to 37 percent as of last Saturday in a daily Gallup survey, the polling company said.

The portion of those interviewed who disapprove of Trump, meanwhile, has risen to 58 percent, according to Gallup.

Both the approval and disapproval marks were at 45 percent on Jan 22, Trump's third day in office, according to the poll.

Gallup has been tracking Trump''s approval rating via daily phone interviews with about 1,500 adults, according to its website.

The poll has a margin of error of three percentage points. Trump has faced difficult poll numbers since before he took office.

A few days before his inauguration, his approval rating stood at 40 percent - about half of the public support his predecessor Barack Obama had, at 78 percent, before his 2009 inauguration, as per Gallup.

The president, however, has rejected the low ratings. "Any negative polls are fake news," he tweeted in early February.

At a press conference last month, Trump cited a poll by Rasmussen Reports that put his approval rating at 55 percent - at a time when Gallup and Pew Research placed his approval rating at 40 percent and 39 percent.

Rasmussen put Trump's approval rating among likely US voters at 48 percent last Friday.

- dpa