No computer is safe, Trump warns, as he casts doubt on Russian hacking attempts

"Because I'll tell you what: no computer is safe. I don't care what they say."

Mr Trump has repeatedly cast aside allegations by US intelligence agencies that Russia tried to influence the presidential election through hacking.

US intelligence services believe Russia ordered cyber-attacks on the Democratic National Committee (DNC), Hillary Clinton’s campaign and other political organizations, in a bid to influence the election in favor of Trump. The US Department of Homeland Security (DHS) and FBI released an analysis of the allegedly Russian government-sponsored hacking groups blamed for the breaches.

Earlier this week Barack Obama ordered sanctions on Russian spy agencies, closed two Russian compounds and expelled 35 diplomats the US accused of being spies.

The Russian government has denied the allegations.

'I know a lot about hacking'

Mr Trump, who has said that he plans to meet intelligence officials next to week to learn more about the allegations, wants them "to be sure because it's a pretty serious charge".

He pointed to intelligence failures over the existence of weapons of mass destruction in Iraq before the US invasion and declared himself an expert in the area.

"I know a lot about hacking. And hacking is a very hard thing to prove, so it could be somebody else," he said.

He added, cryptically, that he also knows "things that other people don't know. And so they cannot be sure of the situation".

During the Trump party, hundreds of guests gathered in the Mar-a-Lago grand ballroom, including action star Sylvester Stallone and romance novel model Fabio. Reporters were invited to watch as guests arrived.

Earlier, Mr Trump gave his press pool the slip, travelling to play golf at one of his clubs without journalists on hand to ensure the public had knowledge of his whereabouts.

A member of his golf club in Jupiter, Florida, posted a photo on Twitter of Mr Trump on the greens on Saturday morning and said about 25 US Secret Service agents accompanied the president-elect. Reporters had not been advised of the visit.

Transition aide Stephanie Grisham confirmed Mr Trump had made a "last-minute trip" to Trump National Golf Club Jupiter, about a half-hour drive from Mar-a-Lago. He returned to the estate at mid-afternoon.

Ms Grisham said that she and other aides were not aware of the trip and "appreciate everyone's understanding".

"We are in the home stretch of this transition period and don't anticipate any additional situations like this between now and inauguration," she said.

Mr Trump, both as a candidate and during the transition, has often scoffed at tradition, such as allowing a group of reporters to follow him at all times to ensure the public knows where he is.

Not long after his election he went out to dinner with his family in Manhattan without informing the pool of his whereabouts.

The practice is meant to ensure that journalists are on hand to witness, on behalf of the public, the activities of the president or president-elect, rather than relying on second-hand accounts.

The White House also depends on having journalists nearby at all times to relay the president's first comments on breaking news.

Trump aides appear to have made an effort in recent weeks to offer additional access, allowing reporters to camp out outside a doorway at Mar-a-Lago to document staff and cabinet candidates' arrivals and departures.

Aides are also providing information about his meeting schedule.

Every president and president-elect in recent memory has travelled with a pool of journalists when leaving the White House grounds.

News organisations take turns serving in the small group, paying their way and sharing the material collected in the pool with the larger press corps.

Before he went golfing on Saturday, Mr Trump tweeted an unusual New Year's message to friends and foes: "Happy New Year to all, including to my many enemies and those who have fought me and lost so badly they just don't know what to do. Love!"

With the arrival of 2017, another New Year's message moved on his Twitter account at about midnight.

This one was decidedly more upbeat and carefully prepared - illustrated with a photo that included his holiday message next to it, including a hashtag and abbreviation referring to his campaign slogan: Make America Great Again.

TO ALL AMERICANS-#HappyNewYear & many blessings to you all! Looking forward to a wonderful & prosperous 2017 as we work together to #MAGA🇺🇸 pic.twitter.com/UaBFaoDYHe

— Donald J. Trump (@realDonaldTrump) January 1, 2017