Pence spoke at day two of the first ever World Summit in Defence of Persecuted Christians where more than 600 persecuted Christians, advocates and church leaders were in attendance.
He told his "brothers and sister in Christ" during his 22 minute speech that: "On behalf of the President of the United States, I say from my heart that we are with you.
"And I'm here on behalf of the president as a tangible sign of his commitment to defending Christians and frankly all who suffer for their beliefs across the wider world."
Pence said that the "Christian faith is under siege" around the world and added to the audience that represented more than 130 countries: "In more than 100 countries spread to every corner of the globe from Iran to Eritrea, Nigeria to North Korea, over 215 million Christians confront intimidation, imprisonment, forced conversion, abuse, assault or worse for holding to the truths of the Gospel.
"In fact, throughout the world the number of Christians facing hostility, persecution and even death is greater than any other time in history.
"As it has been said, the persecution of one Christian affects us all."
The summit is being convened by the Billy Graham Evangelistic Association from 10th-13th May in Washington, D.C.
Meanwhile, Pastor Saeed Abedini who was imprisoned for his faith in Iran and accused evangelist Franklin Graham, the president of the Billy Graham Evangelistic Association of using his story for personal gain has complained he wasn't invited to the summit.
In a Facebook post he Abedini said: "Six hundred people from 130 countries. And I'm not one of them.
"While I was in prison, they spoke about me on their TV and radio shows. They held prayer vigils in my name in DC and all around the country. And yes, they asked you to donate because of my horrible plight.
"And while they tugged at your heart strings to donate, (for which I remain so grateful) I remained in prison, and they remained in their mansions. And their jets. Earning millions off the backs of people like me.
"But once I got released, the story was over. Literally just like that. No one wanted to meet with me."
Abedini was placed under house arrest before being imprisoned for three-and-a-half years in Iran for participating in Christian home churches in 2012.
In a statement to The Christian Post, Graham's public relations team dismissed Abedini's claims of being used and denied raising money for him.
Graham's spokesman, Mark DeMoss, said:"When Franklin Graham first learned that American pastor Saeed Abedini had been imprisoned for his Christian faith in Iran in 2012, he did what millions of people around the world did - he began to pray for his release and for his family here in America.
"He also did whatever he could to draw attention to the plight of this pastor, including speaking personally to President Obama and President Putin about his situation and urging Christians around the world to pray for his release."
Premier has contacted the Billy Graham Evangelistic Association for a comment on whether Abedini was invited to the summit.