A Catholic leader has warned Anglican bishops meeting in Canterbury that divisions between Christians have become an "emergency" in urgent need of addressing.

In a message to the Lambeth Conference, Cardinal Kurt Koch, the Roman Catholic Church's ecumenical lead, said that despite decades of progress in improving relations, urgent steps must be taken to foster greater unity between Christians.

"This ecumenical emergency implies that a sincere and thus common ecumenical witness to Jesus Christ in the present world is only possible when the Christian churches overcome their divisions and can live in unity in reconciled diversity," he said. 

"Ecumenism and mission belong inseparably together since that is the only way in which God´s Church really is for God's World."

Speaking before a plenary on unity, the Venerable Will Adam, the Anglican Communion's former Director of Unity, Faith and Order, said that divisions were wounding the body of Christ.

"Unity is something for which Jesus prayed, and which the Bible teaches us is important – integral even – to the life of the Church," he said.

"When the Church is divided, the body of Christ is wounded."

Bishops have issued a Lambeth Call on Christian Unity committing Anglicans to "an urgent search for the full visible unity of the Church" .

It followed an appeal for unity by the Archbishop of Canterbury, Justin Welby. 

"So let us not treat each other lightly or carelessly. We are deeply divided. That will not end soon. We are called by Christ himself both to truth and unity," he said earlier in the conference.