Footage of former prime minister Tony Abbott staring in silence at the newly unveiled portrait of Julia Gillard has left many wondering what could have possibly been going through his mind.

As fellow politicians, staff and friends of Ms Gillard milled around chatting, Mr Abbott gazed intently at the portrait for some time, before waiting awkwardly on stage for his turn to congratulate the former Labor prime minister.

1 minute of Tony Abbott today #auspol pic.twitter.com/LhB8FBwJru — Gavin Harlow (@HarlowGavin) October 24, 2018

The one-minute video, posted by cameraman Gavin Harlow on Twitter late Wednesday night, has intrigued many on social media.

Tell me this is just a joke by the Robotics Department at ANU! I mean it is, isn't it? Or did Abbott just wander into the scene trying to find his office after an all night bender? #auspol — Gary Fallon (@GaryFallon2) October 24, 2018

Maybe as a socially awkward person this is the most relatable Tony Abbott has been for me. — Josh Taylor (@joshgnosis) October 24, 2018

Some praised the former prime minister for sticking around to congratulate his former foe in the parliament.

Others added their own soundtrack ranging from Cold Chisel's Standing on the Outside to the theme from television show Curb Your Enthusiasm.

It's not Mr Abbott's first long awkward silence caught on camera.

In 2011, the then opposition leader was lost for words when confronted by a reporter with footage of him saying "sh*t happens" while being briefed on the death of a soldier.

As the silence stretched on, Channel 7 reporter Mark Riley pointed out: "You're not saying anything Tony".