Churches Together in Britain and Ireland (CTBI) is asking Christians to come together in prayer for an end to the war in Ukraine.
The ecumenical body has written a prayer for peace and is inviting churches to use it during their Sunday worship on 3 April.
Christians are also being asked to light candles in remembrance of those affected by the "terrible" war.
"We have all watched the unfolding conflict in Ukraine and seen the heart-breaking stories of people fleeing violence, not knowing when they'll see their loved ones again," said CTBI General Secretary Nicola Brady.
"Over two million people have fled Ukraine. Many more have been forced from their homes to seek shelter. Lives have been lost and families torn apart. Homes have been destroyed and many roads are blocked. No one is safe."
She welcomed the "generosity and hospitality" being shown to refugees by churches in the UK and other European countries.
"We all share a feeling of horror and powerlessness but every prayer, every action brings hope to the people of Ukraine," she said.
"Together as Christians in these islands and with our sisters and brothers in the churches of Ukraine, we pray for an end to the conflict and for peace in our world."
CTBI's Prayer for Ukraine:
God of all peoples and nations,
Who created all things alive and breathing,
United and whole,
Show us the way of peace that is your overwhelming presence.
We hold before you the peoples of Ukraine and Russia,
Every child and every adult.
We long for the time
When weapons of war are beaten into ploughshares
When nations no longer lift up sword against nation.
We cry out to you for peace;
Protect those who only desire and deserve to live in security and safety
Comfort those who fear for their lives and the lives of their loved ones
Be with those who are bereaved.
Change the hearts of those set on violence and aggression
And fill leaders with the wisdom that leads to peace.
Kindle again in us a love of our neighbour,
And a passion for justice to prevail
and a renewed recognition that we all play a part in peace.
Creator of all hear our prayer
And bring us peace. make us whole.
Amen.
