The World Evangelical Alliance and European Evangelical Alliance have issued a joint call for prayer to see an end to the war in Ukraine.
Evangelicals are being asked to set aside 24 August - Independence Day in Ukraine - for the day of prayer.
"On this day of independence, we want to declare our dependence on God, the One who can bring true peace to the hearts of each individual person, each family and even entire peoples," said the European Evangelical Alliance (EEA) General Secretary Thomas Bucher.
The day will bring evangelicals together to pray for "an end to the suffering" and "an end to loss of life, an end to destruction and atrocities, and the beginning of healing".
Prayers will also be said for the global repercussions of the war to cease, especially the impact on supplies of grain that are threatening millions of people with famine.
"The effects at the global level continue to be felt as millions of the world's poorest people are threatened with starvation," said Bucher.
"Although there have been some signs of hope with the recent agreement to allow the export of grain from Ukrainian ports, the situation remains a great concern.
"Let us pray that the grain can make its way to the places where it is needed most, so that the most vulnerable are not suffering further consequences of a war that may be half a world away."
The call to prayer includes praying for hearts to be changed and a lasting peace.
"Pray that peace is not sought through weapons but through prayers," he said.
"While the world may continue to look for weapons to bring about peace and justice by force, we know that true and lasting peace can only be accomplished through unceasing prayers.
"As we look to Jesus Christ, the Prince of Peace, let us pray for hearts to be changed and for the weapons to be silenced."
Bucher praised the "heartening" response of evangelicals to people impacted by the war, with offers of practical assistance and taking in displaced Ukrainians.
Families are being encouraged to pray for Ukraine with their children and a kid-friendly prayer guide has been created to help with this.
"Throughout history, God has changed hopeless and dire situations in surprising ways, and He can do it once again," Bucher ended.
"And let us also pray for healing and for reconciliation, and that Russia and Ukraine could live in peace as independent, sovereign nations."