The leader of an organisation accused of being the United States' leading anti-Muslim hate group visited the White House on Tuesday and described her visit as "very productive".

Brigitte Gabriel, a Lebanese American, is the founder of ACT for America. The organisation claims to have half a million members across the US, and 1,000 chapters, and describes itself as a grassroots organisation dedicated to helping "to protect America from terrorism".

It is classified by the Southern Poverty Law Center as an anti-Muslim hate group, working to "advance anti-Muslim legislation at the local and federal level while flooding the American public with wild hate speech demonizing Muslims".

Gabriel posted a picture of herself on Facebook in the White House, and meeting an unnamed official in an ornate room, describing the visit as "very productive".

The White House confirmed the visit, and told the Guardian Gabriel and a colleague visited to "participate in a brief meeting with a member of our legislative staff. The purpose was to make general introductions, which is pretty typical with any new administration".

The official added: "They requested the meeting to share their ideas."

Gabriel, a Christian, fled Lebanon first for Israel, then for the US during its civil war.

She has outlined her controversial views on Islam in public speeches and in publications, and in 2007 told a course at the Department of Defense's Joint Forces Staff College that a "practicing Muslim, who believes in the teachings of the Koran, cannot be a loyal citizen of the United States".

Amongst the group's board members is sacked national security advisor general Michael Flynn, who has described Islam as a "cancer". White House Advisors Steve Bannon and Stephen Miller are also known for their hardline anti-Islam views.

Heidi Beirich, director of the Southern Poverty Law Center's Intelligence Project, said in a statement: "Brigitte Gabriel is an extreme Islamophobe and leader of a known hate group.

"Hate has no place in the White House and she should not have an audience with the Trump administration. There have been enough anti-Muslim people in this administration already – enough is enough."