Mike Waltz, U.S. White House National Security Advisor. /Courtesy of AP Yonhap News

The iPhone's contact update feature appears to have been the catalyst for 'Signal Gate,' which recently trapped the Donald Trump administration in a dilemma.

The British daily Guardian reported on the 6th (local time) that a security team from the White House reached this conclusion after forensically examining the cellphone of Michael Waltz, the White House national security advisor.

Previously, Waltz mistakenly invited Jeffrey Goldberg, the editor of The Atlantic, to a secret chat room discussing airstrike operations by the Houthi rebel group in Yemen on the private messenger Signal.

Subsequently, Waltz clarified that he had never met Goldberg before and had not been in contact with him, indicating that he was unsure why the contact was saved on his cellphone.

The forensic examination of the cellphone by the White House revealed that Waltz's claims were substantiated.

The point at which Goldberg's contact was saved on Waltz's cellphone is estimated to be in October of last year, just before the presidential election.

At the time, Goldberg wrote an article criticizing Trump's stance on veterans and sent an email inquiring about the Trump campaign's position.

Brian Hughes, who served as a Spokesperson for the Trump campaign, forwarded this email to Waltz before handling the response.

The issue is that in the process of Hughes copying the email and sending it via text, Goldberg's phone number included in the email was also shared.

Goldberg's phone number appears to have been saved on Waltz's cellphone through the iPhone's contact suggestion update feature.

The contact suggestion update is a feature that automatically adds numbers deemed relevant by the iPhone's algorithm to existing contacts.

Accordingly, Goldberg's phone number was added to Hughes's contacts, and Waltz mistakenly invited Goldberg to the chat room thinking he was Hughes. Hughes is currently the Spokesperson for the National Security Council (NSC).

Meanwhile, President Trump considered the possibility of dismissing Waltz after the Signal Gate incident, but he is reported to have calmed his anger after being briefed on the cellphone forensic results.