The Archbishop of Canterbury is warning the UK is in danger of 'hiding behind closed doors' and called on churchgoers to 'overcome danger and those who cause danger'.

Justin Welby was speaking at a Pentecost celebration the morning after a terrorist attack killed at least seven people in London on Saturday night.

Addressing hundreds packed into Holy Trinity Church, Folkestone, the Archbishop said the attack plus the bombing in Manchester last week and other conflicts around the world are 'evidence we need difference'.

He said: 'We need the difference Jesus makes, we need the order bought out of chaos, we need the knowledge of an eternal purpose for each of us.

'We need to know that whatever other people do to us, God loves us for ever.'

He added: 'It is not a difference political parties, however sincere and committed, can bring.

'But the difference that has to come is a difference that can only be made possible by God.'

He went on to say the UK's calling was to overcome danger, not hide and withdraw into locked rooms, referring to the Christian festival of Pentecost when the Holy Spirit filled Jesus' disciples when they were hiding in a locked room.

'Locked doors as we saw last night are sometimes a necessity but we must know how to move forward.

'We know those times when we have all felt the same. We might some us be in such times now.

He added: 'There is a risk of our nation becoming a people who flee danger and try and lock themselves away when our culture, our history and our calling is to be those who overcome danger and overcome those who cause danger.'

Earlier Welby tweeted his horror at the attack which has injured nearly 50 people, some of whom are in a critical condition.

The Pentecost service was filmed live on BBC1 and marks the climax of the Archbishop's Thy Kingdom Come celebrations – a worldwide evangelism initiative.

In a rousing opening to his sermon, Welby said: 'The strongest power in the world is the love of Jesus Christ. It is more powerful than the evil of terror or the profound wickedness of the terrorist. It is invisible to most rulers; it is unheard of to most communicators.

'It has no Twitter account, it does not appear on Facebook but it has overcome more nations than the greatest armies, changed more lives than the finest orators and communicators, drawn more people into true community than all the social media there is, has been or ever could be.

'It breaks down barrier between races, it tears the frontiers between nations, it overcomes the oppression between genders, and classes and capacities, wealth or education.

'It is this love that daily transforms my life, our lives and all those who follow Jesus Christ, and the lives of many millions around the world.'