Donald Trump said on Saturday he has not read Robert Mueller’s report about contacts between his 2016 campaign and Russia, which his Democratic opponents say should be released in full.

“I have not read the Mueller report yet, even though I have every right to do so,” Trump wrote on Twitter. “Only know the conclusions, and on the big one, No Collusion.”

The attorney general, William Barr, has said he plans to make public a redacted copy of the special counsel’s near-400-page investigative report into Russian interference in the 2016 election by the middle of this month, if not sooner.

On 22 March, Mueller completed his 22-month investigation. Barr sent a four-page letter to Congress two days later, outlining the main findings. Barr told lawmakers the investigation did not establish that members of Trump’s election campaign conspired with Russia, but also did not exonerate the president on obstruction of justice.

Barr said he had concluded there was not enough evidence to show that Trump committed the crime of obstruction.

Reports this week said members of Mueller’s team were unhappy with the way Barr, a Trump appointee, characterized the report’s conclusions.

Asked in an interview with Fox and Friends Weekend about calls for the release of the full confidential report, Trump said: “It’s really up to the attorney general, whatever he wants to do.”

Trump, who was in Las Vegas for a speech to a Jewish Republican group, was busy on Twitter on Saturday morning. In another tweet, he called the Mueller report “a total waste of time”.

Barr did not meet a demand by Democrats in the House of Representatives to provide the unredacted report to lawmakers by 2 April.

He told Congress in a letter last week he must redact material that was presented to a grand jury, as required by law, as well as information that could reveal US intelligence agencies’ sources and methods. Democrats have indicated they will fight those redactions in court if a subpoena is ignored.

Russia’s government has denied interfering in the US election.