This is the awkward moment Julia Gillard and Tony Abbott came face to face again in Parliament.

But this time it wasn't as party leaders squaring off across the House of Reps.

Instead, the two former rivals met again as a painting of Ms Gillard was unveiled five years after she lost the top job.

Julia Gillard leaves Tony Abbott waiting following the unveiling of her official portrait. (9news)

However, Mr Abbott soon drew some attention after being left waiting for several minutes to greet Ms Gillard.

The former Labor leader spent a good few minutes speaking with Parliament House cleaners as Mr Abbott waited awkwardly in the background to talk to her.

When the two finally shook hands, the encounter was nonetheless a little on the cooler side.

Ms Gillard and Mr Abbott shake hands - finally. (9news)

Before a packed gallery of Labor and Coalition MPs, including another former Prime Minister Tony Abbott, Ms Gillard spoke of her reluctance to have the portrait done, believing it was part of the "pomp and ceremony" of being a nation's leader.

"And I wasn't particularly interested in doing that," Ms Gillard said after being warmly greeted.

"I always said, let's just forget about it, let's just forget about."

But she finally agreed after a little nudge from her staff.

"They said 'you ought to get that portrait done before you look a hell of a lot older than you did as prime minister'," Ms Gillard said.

The former leaders smile for the cameras. (9news)

"I thought yes, I really should get this done."

She said portraits were difficult to capture a prime minister's achievements, the overseas trips, the "sleepless nights" worrying about establishing the National Disability Insurance Scheme, or the Royal Commission into child sex abuse.

The portrait will hang beside John Howard in Parliament House.