The Most Revd Justin Welby and the Most Revd John Sentamu were speaking after 50 people were killed and another 53 injured in a nightclub in Orlando, Florida when an armed man stormed the building shooting.
Authorities say 29-year-old Omar Mateen opened fire with an AR-15 rifle at a gay venue early on Sunday morning before being killed in a shootout with police.
Welby and Sentamu issued a statement that read: "After Sunday's attack in Orlando, as Christians, we must speak out in support of LGBTI people, who have become the latest group to be so brutally targeted by the forces of evil.
"We must pray, weep with those affected, support the bereaved, and love without qualification.
"The obligation to object to these acts of persecution, and to support those LGBTI people who are wickedly and cruelly killed and wounded, bereaved and traumatised, whether in Orlando or elsewhere, is an absolute call on our Christian discipleship.
"It arises from the unshakeable certainty of the gracious love of God for every human being. Now, in this time of heartbreak and grief, is a time for solidarity.
"May God our Father give grace and comfort to all who mourn, and divine compassion to us all."