Former US president Bill Clinton has urged leaders in Northern Ireland to finish the peace building of Martin McGuinness.
Clinton spoke with candour about the political situation in the North and invited a round of applause for Enda Kenny, following the Taoiseach's address in Washington last week.
Large crowds are expected in Derry today for the funeral of Martin McGuinness.
"First and foremost, Martin McGuinness was a much loved husband, father and grandfather", said Mrs Foster.
"He was a man who showed huge courage in all stages of his life, both in his paramilitary days and in the peace process, taking huge risks and offering clear leadership".
Mr McGuinness passed away earlier this week, aged 66.
There was applause inside the church when some politicians arrived, including for ex-first minister and Democratic Unionist Party leader Arlene Foster, who survived an IRA bombing as a teenager and whose father was shot by the IRA.
The face of Irish Republicanism during some of the worst moments of three decades of sectarian bloodshed that killed more than 3,600 people, McGuinness remained a figure of hate for many pro-British Protestants until his death.
Prime Minister Theresa May told parliament she could never condone the ex-IRA commander's violent past but she credited his "indispensable" role in moving the Republican movement away from armed conflict.
Rev David Latimer, of the First Derry Presbyterian Church, said: "Martin has bequeathed to us a better place to live".
She is to send a personal message to Mr McGuinness's family.
He also struck up a warm relationship with the Queen, whom he praised for her contribution to peace.