This Sunday, President Trump is calling on all Americans to pray for the victims of Hurricane Harvey.

While the President and First Lady Melania Trump are scheduled to visit Houston today, he offered the proclamation on Friday.

Titled “National Day of Prayer for the Victims of Hurricane Harvey and for Our National Response and Recovery Efforts,” it begins:

Hurricane Harvey first made landfall as a Category 4 storm near Rockport, Texas, on the evening of August 25, 2017. The storm has since devastated communities in both Texas and Louisiana, claiming many lives, inflicting countless injuries, destroying or damaging tens of thousands of homes, and causing billions of dollars in damage. The entire Nation grieves with Texas and Louisiana. We are deeply grateful for those performing acts of service, and we pray for healing and comfort for those in need.

Americans have always come to the aid of their fellow countrymen — friend helping friend, neighbor helping neighbor, and stranger helping stranger — and we vow to do so in response to Hurricane Harvey. From the beginning of our Nation, Americans have joined together in prayer during times of great need, to ask for God’s blessings and guidance. This tradition dates to June 12, 1775, when the Continental Congress proclaimed a day of prayer following the Battles of Lexington and Concord, and April 30, 1789, when President George Washington, during the Nation’s first Presidential inauguration, asked Americans to pray for God’s protection and favor.

When we look across Texas and Louisiana, we see the American spirit of service embodied by countless men and women. Brave first responders have rescued those stranded in drowning cars and rising water. Families have given food and shelter to those in need. Houses of worship have organized efforts to clean up communities and repair damaged homes. Individuals of every background are striving for the same goal — to aid and comfort people facing devastating losses. As Americans, we know that no challenge is too great for us to overcome.

“Melania and I are grateful to everyone devoting time, effort, and resources to the ongoing response, recovery, and rebuilding efforts,” the proclamation reads.

“We invite all Americans to join us as we continue to pray for those who have lost family members or friends, and for those who are suffering in this time of crisis.”

On Thursday, Second Lady Karen Pence led prayer for victims while she was in Texas with the Vice President.

She called the first responders and those helping to save lives “an inspiration.”

“We pray your blessing on the state of Texas and Louisiana as they go through some hard days,” she said.