US President Donald Trump ordered an investigation Wednesday into former President Joe Biden's presidential actions, alleging his top aides helped "conceal Biden's cognitive decline."

The memorandum specifically directs White House Counsel David Warrington in consultation with Attorney General, Pam Bondi, to carry out the review, taking particular issue with Biden's use of what is known as an autopen to sign official documents. An autopen is a machine used to sign documents.

It alleges that Biden's aides not only used the device to sign critical documents, including pardons, but "severely restricted" his press conferences and "scripted" conversations with lawmakers and officials "all to cover up his inability to discharge his duties."

"In recent months, it has become increasingly apparent that former President Biden's aides abused the power of Presidential signatures through the use of an autopen to conceal Biden's cognitive decline and assert Article II authority," Trump said in his memorandum, referring to the article of the US Constitution that established the executive branch.

"This conspiracy marks one of the most dangerous and concerning scandals in American history. The American public was purposefully shielded from discovering who wielded the executive power, all while Biden's signature was deployed across thousands of documents to effect radical policy shifts," he added.

The former president did not immediately have a public statement in response to Trump's memorandum.

But in an action apparently coordinated to coincide with Trump's announcement, House Oversight Committee Chairman James Comer expanded his own investigation into Biden's mental acuity by sending letters to five former senior Biden officials, including former senior advisors Michael Donilon and Anita Dunn, former Chief of Staff Ronald Klain, Deputy Chief of Staff for Policy Bruce Reed and former Counselor Steve Ricchetti.

"The cover-up of President Biden?s mental decline is one of the greatest scandals in our nation?s history. These five former senior advisors were eyewitnesses to President Biden?s condition and operations within the Biden White House," he said in a statement.

"They must appear before the House Oversight Committee and provide truthful answers about President Biden?s cognitive state and who was calling the shots," he added. (Anadolu Agency)

Update news