'Too busy': Sydney siege hostage furious over Tony Abbott's response to Monis demands

A Sydney siege hostage has told an inquest that she was furious when then-Prime Minister Tony Abbott refused to speak with gunman Man Haron Monis because he was "too busy".

"I didn't understand why it was so difficult for the prime minister to get on the phone," Marcia Mikhael told the inquest.

"I was told, 'sorry Marcia, the prime minister is a very busy man'," Ms Mikhael said, explaining she felt at that moment the lives of those inside the Lindt café were "not worth saving".

"I'm sorry but you don't tell someone who has a gun at their head that. I'm going to feel like I'm a piece of nothing and I'm going to die. Just pick up the phone!"

During her testimony, Ms Mikhael also revealed how she thought Monis's actions on that fateful morning of December 15, 2014, were part of a prank of some kind.

She and two colleagues didn't even have time to finish their coffees before Monis pulled a sawn-off shotgun from a blue bag and ordered staff to lock the cafe's doors and announced that no one would be leaving.

"I thought Channel Seven was going to come out of the kitchen and say 'prank'," she said Tuesday.

But it was not a joke and while brandishing a shotgun Monis ordered people to leave their mobile phones on a table and arranged the hostages to stand at windows around the cafe.

Ms Mikhael said she thought Monis had done this to give himself protection and prove the siege was serious.

Ms Mikhael was moved near the front doors where she stood looking out of the cafe, terrified of the scene unfolding behind her.

"I was frozen in fear," she said.

As she stood at the doors Senior Constable Paul Withers, the first officer to arrive, managed to catch her attention without alerting Monis.

He gestured to Ms Mikhael and encouraged her to calm her breathing, which she said helped her cope.

"I would like to thank him," Ms Mikhael said.

The inquest continues.