Washington (AFP) - US President Donald Trump is enjoying the strongest polling of his presidency following the release of special counsel Robert Mueller's report and positive economic news, according to public opinion poll agency Gallup.

Trump's job approval rating crept up one point to 46 percent for the two-week period ending April 30, a substantial rise from the 39 percent approval he recorded in early March.

"In addition to the initial interpretation of the Mueller report, which Trump claimed vindicated him from charges that he had colluded with Russia, the economy has offered several reasons for Americans to look more favorably on Trump," Gallup said late Friday.

Trump remained underwater in Gallup polling, however, with disapproval of his performance at 50 percent, although down from 57 percent on March 10.

The polling was conducted before it was revealed that Mueller had written to US Attorney Bill Barr to complain how Barr summarized the investigation's findings.

It also preceded Barr's refusal to testify before a House panel, and came before Democrats threatened to hold Barr in contempt for failing to turn over a full unredacted version of Mueller's report on Russian 2016 election interference.