Following Baroness Sayeeda Warsi's shock resignation, Communities Secretary Eric Pickles is to take up her responsibilities as Faith Minister.

Pickles, who caused controversy in April this year when he declared that atheists should accept that Britain is "a Christian nation" and "get over it", was thanked by Lady Warsi in her resignation letter to the PM.

"Eric Pickles has supported me tirelessly in our work on combating hate crime, challenging anti-Semitism and Islamaphobia and the pioneering work of celebrating faith in the public sphere," she wrote.

"This new found confidence in Government has allowed me to take the very public International lead on religious freedom, specifically on the ever growing crisis of persecution of Christians."

A letter from David Cameron in response to her resignation thanks Warsi for her support while in government, and notes that her partnership with Pickles "played an important role in the Government's integration agenda – building more united communities, tackling hate crime, harnessing the power of faith groups and championing Britain's common heritage."

Pickles, who praised Lady Warsi on Twitter yesterday, has already publicly tweeted his support for the government's work with faith groups.

The link Pickles provided shows an infographic with ways in which the power of faith groups has been harnessed by Cameron's policies, including making "the persecution of Christians and minorities abroad a Human Rights priority" and investing £1.1 million in an Inter Faith Network "to promote strong and sustainable relations between different faith communities."

Pickles has personally been keen to warn against the "intolerance of aggressive secularism" while in office.

"In recent years long-standing British liberties of freedom of religion have been undermined by the intolerance of aggressive secularism: taking people to task for wearing a cross or a rosary, beginning costly legal actions against council prayers – as if they had nothing better to do," he declared in a speech last year.

Lady Warsi left her post over disagreement with government policies towards the escalating crisis in Gaza.

"My view has been that our policy in relation to the Middle East Peace Process generally but more recently our approach and language during the current crisis in Gaza is morally indefensible, is not in Britain's national interest and will have a long term detrimental impact on our reputation internationally and domestically," she explained.

"I always said that long after life in politics I must be able to live with myself for the decisions I took or the decisions I supported. By staying in Government at this time I do not feel I can be sure of that."