The Alliance of Evangelistic Ministries, which is backed by Christian leaders, is gearing up for the International Day for the Unreached on May 15, an event that seeks to spread the Gospel to over two billion people across the globe.

Evangelical leaders such as Pastor Rick Warren of Saddleback Church have been busy encouraging Christians to take part in the one-day event, according to CBN.

"With more than two billion people who haven't had a chance to meet Jesus, it's time for the Body of Christ to take a radical stand and say, 'This has to end in our generation.' Join me in committing to pray, give, go, and advocate for those who need to know Christ by participating in the International Day for the Unreached," Warren urged.

The event will be sponsored by the Alliance for the Unreached, a religious group that has the backing of Reach Beyond, Bibles For The World, Operation Mobilization, The Seed Company, and Missio Nexus.

"In America, it's easy to get comfortable and complacent. But we want to remind people that there are literally billions of people around the globe in desperate need of the good news of Jesus but have never heard His name or story. We're called to bring it to them," Wayne Pederson, president of Reach Beyond, said in a statement.

Missio Nexus' senior vice president Marvin J. Newell, on the other hand, believes now is a "crucial" time to spread the Gospel, given the religious, political, and cultural turmoil faced by the world.

"The International Day for the Unreached comes at a time when Europe is crowded with refugees from countries without a Christian heritage, when the comfort and hope offered by the Gospel would be especially appreciated," Newell said.