Malcolm Turnbull prepares to take office

Malcolm Turnbull insists he wasn't expecting to become prime minister, but he's looking forward to leading a strong government.

Leaving his Canberra apartment the morning after defeating Tony Abbott in a Liberal leadership spill, Mr Turnbull told reporters he was filled with optimism.

"There has been a change of prime minster but we are a very, very strong government," he said.

When asked if it was a dream come true, Mr Turnbull said he did not expect Monday's turn of events.

"But it's one that I'm privileged to undertake and one that I'm certainly up to," he said.