Premier understands Most Revd Justin Welby made the comments in an exclusive interview with Imed Dabbour, a journalist from the Middle East and North Africa's biggest Christian television network, SAT-7.
On Premier's 'News Hour' Imed Dabbour revealed some of the details covered in the discussion at Lambeth Palace: "He (Justin Welby) said 'as Westerners we have some understanding to what's happening to this radical movement, but it's people within Islam; they need to deal with it. We can help, as Christians we can help through dialogue; with respect.
"He talked a lot about love and respect but he also was saying 'firmly I'm a Christian and my Christian faith is to show the truth in my perspective, dealing with radical Islam, it needs to come from inside'."
"You can help with logistics, you can help with building bridges, showing love, helping liberal Muslims... to deal with the issue and to face it," Mr Dabbour added.
The interview came on the same day a defector from Islamic State gave an interview saying he saw British-born militant Mohammad Emwazi, known as 'Jihadi John', behead the Japanese Christian journalist Kenji Goto.
The defector, known only as Saleh, is the first to publicly admit actually seeing a killing take place in an Islamic State video.
The UK's role in fighting Islamic State extremists was recently described as "strikingly modest" by MPs who suggested it should be stepped up.
The Defence Select Committee found the UK had carried out 6% of coalition air strikes against the jihadist group and said it was "surprised and deeply concerned" it was not doing more.
The government said military action was just part of "comprehensive" action by the international US led coalition.
Listen to Imed Dabbour speaking to Premier's Des Busteed live on the News Hour:
