Acknowledgement receipt and other documents the Constitutional Court had sent to President Yoon Suk Yeol regarding his impeachment trial, were returned after three rounds of visit by the post office.

At a press briefing, the court's public information officer Lee Jin said the documents that were approved by the court on Monday were mailed for the second time on Wednesday.

The Presidential Security Service at Yoon's official residence refused to receive the documents, while they could not be delivered to the presidential office due to the absence of the recipient.

The post office attempted delivery for the third time on Thursday, but they were once again refused and returned for the same reason, prompting the court to send the documents to the presidential residence yet again.

The court's warning for Yoon to submit the minutes from a Cabinet meeting that preceded the December 3 martial law decree has also yet to be delivered.

The court is expected to announce next Monday how it will regard the failed document deliveries, and how that would reflect in the trial proceedings, and consider other avenues including the possibility of leaving them at the delivery location or whether to consider them as completed delivery after sending via mail.