WASHINGTON — A group representing President Donald Trump’s transition team says a memo in the hands of the General Services Administration should have stopped the agency from turning over tens of thousands of e-mails to the special counsel investigating Russian meddling in the 2016 election.

A lawyer for Trump for America said in a letter to GSA that a cache of transition e-mails the agency delivered last August to Robert Mueller’s investigators was actually owned and controlled by the transition. The transition claims it believes a GSA official communicated that warning in a memo to Mueller’s investigators before the special counsel took possession of the e-mails.

The transition group’s letter, obtained Wednesday by The Associated Press, asked GSA to find the memo under the federal Freedom of Information Act and turn it over to Trump for America. GSA provides workplaces, goods and services for federal agencies.

Trump for America general counsel Kory Langhofer did not explain in the letter how the group was made aware that the GSA memo exists but said “it is our understanding” the document was sent in June by the GSA’s top lawyer, Richard Beckler, to Mueller’s team. Beckler has since died.

“The GSA had no right to access or control the records but was simply serving as Trump for America’s records custodian,” Langhofer wrote in the letter delivered Monday. He added that the GSA “unlawfully” handed over “thousands of private and privileged (presidential transition team) e-mails to the Special Counsel’s Office, and failed to notify (Trump for America) of the production.”

GSA spokeswoman Pamela Dixon declined Wednesday to comment on the letter. Peter Carr, spokesman for the special counsel, also declined to comment, citing an earlier statement that when the counsel’s office obtains e-mails during its investigations “we have secured either the account owner’s consent or appropriate criminal process.”

In September, investigators for Mueller obtained tens of thousands of e-mails that related to 13 senior Trump transition officials. Among them was former national security adviser Michael Flynn, who pleaded guilty to one count of making false statements to FBI agents in January and is now cooperating with Mueller’s investigation. Flynn was fired by Trump in February for misleading senior administration officials about his contacts with Russia’s ambassador to the U.S.

Mueller so far has indicted two other Trump campaign officials and a fourth has pleaded guilty to lying to the FBI.

Ken Nahigian, Trump for America’s executive director, said the transition made the records request to respond to GSA’s role in the “unlawful seizure of Transition documents by Mr. Mueller.”

Nahigian said the agency’s cooperation with the special counsel without the knowledge of the transition “will irreversibly chill the operations of future presidential transition teams.”

The GSA in recent years has provided office space, phones and computers to presidential transition teams. After Trump’s presidential election victory in November 2016, his transition officials relied on the federal agency’s site to host and archive its electronic communications. The transition’s e-mails were slated for deletion after Trump’s inauguration, but the transition asked the GSA to retain the records after receiving document requests from Congress last spring.

Some criminal law experts have expressed skepticism about the transition’s claims to legal ownership of the e-mails, but Langhofer and other transition officials insist that Beckler had agreed with Trump for America both in phone conversations and in the sought-after memo that the e-mails belonged to the transition.

Langhofer said that Beckler “acknowledged unequivocally” that the transition team “owned and controlled” the e-mails and that the GSA “was simply serving as TFA’s records custodian.” In Beckler’s absence last August, his deputy, Lenny Loewentritt, made the decision to turn over the trove of transition e-mails to Mueller’s team — without notifying Trump for America, Langhofer said.

Associated Press writer Chad Day contributed to this report.