High-level Australian Federal Police (AFP) operations in Sydney, including potential cocaine importation drug bust operations, have been imperilled by increased security needs, including at the Prime Minister's personal residence.

Key points: 23 AFP operations had to be transferred, moved or cancelled because of a lack of capacity

23 AFP operations had to be transferred, moved or cancelled because of a lack of capacity AFP transferred 102 drug importation cases of more than 1kg to NSW Police

AFP transferred 102 drug importation cases of more than 1kg to NSW Police The document cited three primary causes, including security at Malcolm Turnbull's Point Piper residence

An internal AFP document from a senior NSW-based officer written in July, and seen by the ABC, said under-resourcing caused by an over-stretched workforce meant 23 operations had to be transferred, moved or cancelled because of a lack of capacity.

The July AFP memo revealed resourcing shortages left the AFP unable to properly investigate a 1.6-tonne cocaine importation, leaving it to be handled offshore.

This meant the operations of an Australian-based crime group behind the import could not be fully explored.

The senior officer wrote that AFP transferred 102 drug importation cases of more than 1kg to NSW Police.

The document cited three primary causes, including Project Rampart, a $40 million program to fortify security at the AFP's capital city buildings, and guarding Prime Minister Malcolm Turnbull's residence at Point Piper.

Security has been bumped up at Prime Minister Malcolm Turnbull's Point Piper residence. ( AAP: David Moir )

The document, which refers to decisions made by the NSW Regional Operations Capacity and Capability Committee, said the equivalent of 22 full-time AFP officers had been diverted to these new duties, the equivalent of three investigative teams.

Chief Andrew Colvin told a Senate hearing the AFP was daily suspending "matters" when it was deemed capacity was lacking. ( AAP: Lukas Coch )

The reduced resourcing left the NSW AFP under strain, the document said, noting Sydney was the critical focus point for high threats, foreign organised crime and terrorist activity.

Unscheduled leave absences have increased by 13 per cent and sustained pressures are causing officers to fall asleep on duty due to fatigue, because of overtime on Project Rampart operations and Point Piper duties.

The document said NSW AFP did not have the sufficient resources to meet the operational load and was beginning to buckle under operational load and inadequate resourcing.

AFP Commissioner Andrew Colvin on Tuesday told a Senate hearing the AFP was daily suspending "matters" — including drug seizures — when it was deemed capacity was lacking.

He said some examples of activities that staff had been diverted to included "supplementing staff at the Prime Minister's residence, it could be Kirribilli House, it could be official establishments like Garden Island or it could be our own location, our own officers in Sydney".

Turnbull rejects accusations of shortages

The Federal Opposition grilled Mr Turnbull about AFP resourcing during Question Time.

"Does the Prime Minister consider the AFP is wrong when it says resourcing shortages left the AFP unable to investigate a 1.6-tonne cocaine importation?" Opposition Leader Bill Shorten asked.

"And when will the Prime Minister finally stop blaming everyone else and finally take responsibility for decisions that his government makes?"

Mr Turnbull rejected accusations of resource shortages, and said the agency had seized record quantities of illegal drugs under the Coalition.

"I value the advice of the AFP Commissioner, Andrew Colvin, I spend a lot of time with him," Mr Turnbull said.

"I take his advice carefully and he knows that when he needs support from my Government to keep Australians safe he can count on that support."

In a statement issued late this afternoon, the AFP said it was "disappointed" information about daily operations had been made public and advised an investigation was underway with its Professional Standards wing.

"The AFP is disappointed an internal working document, which sought to provide confidential operational advice and revealed operational sensitivities, has been made public as this undermines the AFP's ability to ensure its resources are used efficiently, effectively and appropriately," the statement said.

"The AFP makes decisions daily on operational priorities, resourcing and determining which matters pose the greatest risk to the safety and security to the Australian community, and directing its resources where they are most needed.

"The provisions in place for Prime Minister Turnbull are entirely consistent with both the current enhanced security environment and protection measures in place for previous prime ministers."