Pupils taking religious studies in Muslim, Hindu, Jewish and other faith schools will be taught to recognise that the religious traditions of the UK are mainly Christian, under Government proposals published today. They will also in future have to study at least two faiths, and will be taught to do critical analysis of texts and to understand "change over time".

Currently faith schools can teach just their own beliefs, but under the reforms they will have to teach another religion as well.

Not just RE but all GCSEs and A levels are being examined to ensure students are better prepared for further education and employment. Computer science, history, languages, dance and mathematics are among the other subjects already looked at.

The reforms also come in the wake of the so-called Trojan Horse plot, when religious extremists were accused of attempting to take over schools. The schools concerned were not faith schools.

"The main change to the religious studies GCSE content is the expectation that all students must study two religions," says the consultation document published on the Department for Education website. "However, students will have the option to spend up to three quarters of their time studying one religion (if textual studies is taken into account). This will ensure all students have a well-rounded education that leads to a rigorous qualification thorough grounding in religion, religions and belief."

The document says the aim is to ensure all students have a thorough grounding in religion, religions and belief. It is in line with other reformed subjects, such as history, where students have to study more than one period of history and need to show a deep and broad historical understanding.

The change to the number of faiths studied also reflects current teaching in most schools, including many faith schools, which already teach more than one religion.

The document says: "The content also sets out the expectation that students recognise the diverse range of religious and non-religious beliefs represented in Great Britain and the fact that the religious traditions of Great Britain are, in the main, Christian. This will help to ensure that students develop respect and tolerance for those with different religions and beliefs."

Students will also be expected to know how to carry out textual analysis of religious texts, which means that in the context of exams, they will have to use proper scholarly methods to explain the source and provenance of religious texts. The document says: "All students will now be expected to study the beliefs and teachings of at least one religion in depth through a systematic study of that religion and/or a detailed analysis of its texts." In addition, they will have to understand "change over time" and be able "critically" to engage with the ideas and arguments of academics, scholars and thinkers.

The document adds: "To encourage greater respect and tolerance students will also be expected to engage in debate in a way that is respectful of the right of others to hold a different view."

The new religious studies GCSE and A level will be introduced from September 2016. The document says the reforms are a response to concerns from higher education institutions that students lack the skills they need to complete a degree.

The Catholic Education Service welcomed the proposals.

Archbishop of Liverpool Malcolm McMahon, chairman, said: "Theologically rigorous RE is a core part of Catholic education. These reforms to GCSE RE and A Level RE provide us with an opportunity to ensure that Religious Education at GCSE and A Level in Catholic schools is academically and theologically rigorous in accordance with Canon Law."

Catholic schools account for 25 per cent of the entries at RE GCSE and 20 per cent of the entries at RE A Level. "As the single largest provider of entries to both RE GCSE and RE A Level, we have worked in partnership with the Government to ensure that these proposals are fit for purpose in Catholic schools. We welcome the assurances from the Secretary of State that these proposals do not undermine the autonomy of the Catholic Bishops to determine and inspect religious education in Catholic schools.

"All Catholic schools are required by Church teachings to raise pupils' awareness of the faith and traditions of other religious communities in order to understand and respect them. These new proposals will facilitate Catholic schools in this duty."

RE must make up at least 10 per cent of curriculum time in a Catholic school and is inspected separately under long-standing arrangements currently set out in the 2005 Education Act.

Rev Nigel Genders, chief education officer for the Church of England, said: "Looking at the world today, it is hard to overstate the importance of equipping the young people of this country with a challenging and rigorous education which includes religious literacy. That is why it is so important that we get these changes right."

As well as studying key scripture and religious texts, students will be able to study criticisms of religion and atheistic world views through the study of philosophy and ethics.

Nick Gibb, minister of state for school reform, said the requirement to learn about more than one faith will help prepare students for life in modern Britain. It will "foster an awareness of other faiths and beliefs, and encourage tolerance and mutual respect - key British values that are non-negotiable and a vital part of a secure future for Britain."

In 2014, Religious Studies had the highest number of GCSE entries after English, Maths and Science.

Ed Pawson, chair of the National Association of Teachers of Religious Education, said: "Religious Studies examination subjects at GCSE and A level have been a massive success story in our schools in recent years. Above all this has shown that young people are interested in engaging deeply with religious, philosophical and ethical ideas."

Dr Joyce Miller, chair of the Religious Education Council, said: "The REC Board has agreed unanimously that the optional systematic study of a non-religious worldview should be introduced at GCSE level. We want to promote a rigorous and inclusive study of religions and beliefs that is relevant and challenging for young people of all faiths and none."