Republican presumptive nominee Donald Trump is to meet with prominent evangelical leaders, according to Fox News.

He has had a mixed press from evangelicals so far in his campaign winning backing from figures such as Robert Jeffress, pastor of First Baptist Church, Dallas, but vitriolic criticism from respected commentators such as Russell Moore, head of the Southern Baptist Convention's Ethics and Religious Liberty Commission.

The meeting is scheduled for June 21 in New York City. As many as 500 conservative leaders are expected to attend. It has been convened by senior evangelical figures including Southern Baptist Convention President Ronnie Floyd, James Dobson, Tony Perkins, president of the conservative activist group the Family Research Council, and mega-church pastors Jack Graham and Ed Young.

Perkins said: "Our goal is to be able to have a conversation that could lead to a better understanding of what Donald Trump has to offer to the country."

He told Fox: "I want to be actively supportive of a candidate who can help turn this nation around. With Trump – I'm not there yet. I hope to be there – but I'm not there right now."

Perkins said Trump will not be delivering a speech but would answer questions from the audience. The meeting would not include a straw poll and there would be no endorsement from the conservative leaders.

Among the issues expected to be raised are Trump's policies regarding religious liberty, pro-life issues and possible vice presidential candidates.

"A vice presidential pick is going to be very crucial," Perkins said. "Mr Trump doesn't have a track record – so I am going to rely very heavily on who he is going to pick as a running mate."

SBC president Ronnie Floyd told Fox: "The vast majority of Southern Baptists are very much where I am today – we're trying to figure this out. We're trying to navigate through these waters that are very uncertain and very difficult."

He urged Christians to vote, saying: "We cannot change what exists or even alter it or adjust it sitting on the sidelines and prognosticating about the situation.

"We have a biblical responsibility, but we also have a responsibility as citizens of the United States to express the privileges afforded to us – that men and women have died on the battlefield to give us – and I'm not walking away from that."

He added: "None of us have endorsed Mr Trump, nor have we condemned Mr Trump. This is about the possibility of being able to appoint the next four Supreme Court justices. This is about the dignity of human life from the womb to the tomb. This is about religious freedom. I'm not about to sit at home and not express something. I'm accountable to God and I believe I'm accountable to my fellow Americans."

It is not known whether Russell Moore, who said that for evangelicals to back Trump they must "repudiate everything they believe", will be in attendance.