WASHINGTON - US President Donald Trump is disappointed with the performance of White House press secretary Sean Spicer and regrets hiring him, CNN has reported, citing multiple sources.

The US broadcaster says the White House is ramping up efforts to find a new communications director in an effort to lighten Spicer's load.

Spicer has served as both White House press secretary and communications director for the new administration - roles which are typically filled by two staffers, says CNN.

Former Trump transition spokesman Jason Miller was originally tapped to serve as communications director for the White House, but Miller stepped aside before Inauguration Day to spend more time with his family.

A longtime Republican operative, Spicer is a close ally of White House chief of staff Reince Priebus. According to the source close to the hiring process, Trump is upset with Priebus over the selection of Spicer for arguably the administration's most visible position, next to the President, says CNN.

"Priebus vouched for Spicer and against Trump's instincts," the source told CNN.

The President "regrets it every day and blames Priebus," the source added.

But a senior administration official says Trump supports Spicer "100 per cent", CNN said.

A separate West Wing source pushed back on the notion that Spicer is suddenly unpopular with Trump, saying "nothing could be further from the truth."

Multiple sources told CNN that Spicer was not Trump's first choice for press secretary.

White House counsellor Kellyanne Conway was offered the position but turned it down. Other candidates including Fox News personality Kimberly Guilfoyle were interviewed for the job during the transition.

Spicer did not respond to a request for comment, CNN said.

He has come under withering criticism during his first two weeks in the job. In his first appearance in the White House briefing room on the President's first full day in office, Spicer berated reporters, accusing them of intentionally downplaying the size of the crowd at Trump's inauguration.

But in his criticism of the media, Spicer used incomplete data and dubious assertions in making his case.

Conway later brushed off criticisms of Spicer, saying the press secretary was utilising "alternative facts," a phrase that went viral in social media.

Over the weekend, Spicer was played by comedian Melissa McCarthy in a scathing skit on the daily White House press briefing on Saturday Night Live. The President, sources say, was not amused by the performance.

The White House is looking at outside candidates to serve in the role of communications director, the source familiar with the process said.

"Needs to be filled more than ever," the source said.