Donald Trump is reportedly shunning security advice by using at least two iPhones, refusing to allow some of them to be screened for hacking attempts because it is “too inconvenient”.

The US president, who has not used email while in office, has one iPhone capable only of making calls and another that is used as his Twitter phone, with access to a series of news sites and the social network, according to White House officials talking to Politico.

While his call-capable iPhone is issued by White House staff and is swapped out “through routine support operations” to check for hacking and other security concerns, Trump has resisted attempts to do similar for as long as five months with his Twitter phone, saying it was “too inconvenient”.

A US president has the power to override White House policy and disregard advice, but given that the devices and systems they use are prime targets for foreign intelligence agencies, doing so can pose significant US national security risks.

Trump’s predecessor, Barack Obama was famed for his love of his BlackBerry before taking office and had a specially modified phone made for him, which lacked a microphone, camera or GPS. Even then this special “military grade” phone was handed over every 30 days to be examined for security risks.

Security officials are concerned that Trump’s disregard for White House protocols have made him a softer target for sophisticated nation-state cyber-espionage, particularly when dealing with the likes of Russia and China.

It’s unclear to what lengths Trump’s Twitter phone has been hardened, but no device is truly unhackable when it is made the target of nation states, despite advances in smartphone security. It is not inconceivable that Trump could fall victim to hacking through Twitter or similar and have his device compromised.

The White House banned its employees from using personal phones while in the West Wing in January. A statement at the time said that the “security and integrity of the technology systems at the White House is a top priority for the Trump administration”.

The personal smartphone of Trump’s chief of staff John Kelly was reportedly hacked during the Trump transition, but wasn’t replaced until October.

Trump also repeatedly criticised rival Hilary Clinton for her use of a personal email server, when at least six senior Trump administration figures did similar things, including Jared Kushner.