It could take a generation to dispel violent extremism from groups such as Islamic State (IS), according to Foreign Minister Julie Bishop.

In a wide-ranging speech, Ms Bishop outlined her concerns about the extent of extremist ideology and the measures Australia is taking to combat it.

"We have no choice but to be part of this struggle against extremism in all its forms — both at home and abroad," she said.

"This will take years, decades, potentially a generation to resolve."

Ms Bishop said the growth of groups such as IS, also known as Daesh, "poses a challenge to global security" and that it was "an issue that keeps me awake at night".

The concern has led Australia to increase funding for security and intelligence agencies and step up its military role in the Middle East.

Ms Bishop also pointed to an expansion on intelligence sharing.

"Our intelligence agencies — and I'm not giving anything away here, I'm sure — are making contact with intelligence agencies from countries that we would not have in the past shared information with," she said.

"The saying 'The enemy of my enemy is my friend" is emerging to be somewhat appropriate in this regard."

She also thanked Muslim community leaders for helping the Federal Government combat terrorism.

"Our Muslim community — its leaders, its mosques — play an important role in combating extremism," she said.

"I thank Muslim community leaders for their vital support."

Her comments stand in contrast to the Prime Minister's recent remarks about the same issue in a speech on national security.

Tony Abbott was criticised by the Islamic community for saying, "I've often heard Western leaders describe Islam as a 'religion of peace', I wish more Muslim leaders would say that more often, and mean it".

More than 200,000 calls have been made to the National Security Hotline in recent times.

Bishop flags difficulty prosecuting those responsible for MH17

Ms Bishop also spoke candidly about the difficulty of prosecuting anyone in relation to the downing of flight MH17 over eastern Ukraine last year.

A report is being prepared into the cause of the crash and Ms Bishop is certain it will show the Malaysia Airlines flight was downed by a surface-to-air missile.

The crash killed all of the nearly 300 people on board, including 27 Australians.

Ms Bishop has suggested it would be hard to pursue Russian-backed rebels if they were found to be the perpetrators.

"I feel sure that whoever ordered that firing, and whoever carried it out, long disappeared into a Russian winter," she said.

"So it will be very challenging for us to take it any further."