WASHINGTON — President Donald Trump says he is not considering firing special counsel Robert Mueller, but that didn’t stop him from adding to the growing conservative criticism of Mueller’s acquisition of thousands of emails sent and received by Trump officials before the start of his administration.

The disclosure came in a letter sent to two congressional committees by Kory Langhofer, general counsel of Trump’s still-existing transition group, Trump for America.

In the letter to the Republican heads of the House Oversight and Senate Homeland Security panels, Langhofer said Mueller’s investigators obtained the emails from the General Services Administration, a federal agency that stored the material, rather than requesting them from the transition organization.

Langhofer asserted the GSA improperly provided the transition records to Mueller’s team, which he said has been “actively using” the emails. In the letter, Lanhofer also contends that the disclosure by GSA was “unauthorized,” and said the transition organization considers the documents private and privileged — and not government property.

While conservatives have been critical of Mueller’s probe of Russian activities during the 2016 campaign, Trump said Sunday afternoon that he has no plans to fire Mueller.

The president did criticize the fact that Mueller had gained access the emails, however. Trump said it was “not looking good” and again stressed that there was “no collusion” with Russia — an important question the probe is examining.

The documents were provided to Mueller’s team by the GSA in September in response to requests from the FBI, but the transition team didn’t learn about it until last week, Langhofer said.

The tens of thousands of emails in question pertain to 13 senior Trump transition officials. Many of the emails that Mueller’s investigators have now include national security discussions about possible Trump international aims as well as candid assessments of candidates for top government posts, said those familiar with the transition. They spoke to The Associated Press on condition of anonymity because of the records’ sensitivity.

Langhofer also said that a GSA official appointed by Trump in May had assured the transition in June that any request for records from Mueller’s office would be referred to the transition’s attorneys. According to Langhofer, the assurance was made by then-GSA General Counsel Richard Beckler, who was hospitalized in August and has since died. A copy of the letter was obtained by the AP.

But late Saturday, another GSA official present for the conversation told Buzzfeed News that there was nothing improper about the disclosure of the emails to Mueller’s team. The GSA has provided office space and other aid to presidential transitions in recent years and typically houses electronic transition records in its computer system.

GSA Deputy Counsel Lenny Loewentritt, whom Langhofer blames along with other GSA career staff for providing the transition documents to the FBI, told Buzzfeed that Beckler didn’t make a commitment to the transition team that requests from law enforcement for materials would be routed through transition lawyers.

Transition officials signed agreements that warn them that materials kept on the government servers are subject to monitoring and auditing, Loewentritt told Buzzfeed, and there’s no expectation of privacy.

Late Saturday, Mueller’s spokesman, Peter Carr, said the special counsel’s office has followed the law when it has obtained documents during its investigation.

“When we have obtained emails in the course of our ongoing criminal investigation, we have secured either the account owner’s consent or appropriate criminal process,” Carr said.

In a statement, Rep. Elijah Cummings of Maryland, the ranking Democrat on the House Oversight and Government Reform committee, dismissed the transition’s arguments that GSA shouldn’t have turned over the records to Mueller. — AP