Bishop Michael Nazir-Ali has criticised the West's reticence on violence against Christians and other minority communities in the Middle East, South Asia and other parts of the world.
Writing in the latest edition of Standpoint magazine, the bishop said the UN had taken the necessary steps to protect people in Libya from attacks by their own government, but questioned why the UN or the West was "unable to tackle the widespread and growing persecution of Christians?"
He voiced particular concern over Iraq, Pakistan and Afghanistan, where the Christian communities face regular attacks and harassment at the hands of Muslims.
"In the case of Iraq, why is there so much resistance to a declaration that Christians, Mandaeans, Yazidis and other minorities need to be protected and that, where necessary, their safety in certain zones will be guaranteed by the international community?" he said.
The bishop suggested that international guarantees would give Christians in Iraq greater confidence concerning their future in the country. Without that, he said that the only option available to them at present was to flee the country.
"If the continued presence of these ancient communities is to be safeguarded, the international community needs to act now."
He warned that Christians were facing a similar situation in Pakistan but with the added difficulty of legally enshrined discrimination.
He said that the country's controversial blasphemy law was an example of the "blatant intolerance" of religious minorities.
He suggested a rethink of Western aid to Pakistan to address extremism.
"Pakistan is the recipient of massive aid from Western countries. This is to assist with basic services and to prevent the spread of extremism. But why should it not be targeted, first and foremost, at those areas which are most susceptible to extremist influence?"
He said Western aid should be used to remove the teaching of hate from textbooks, to reform the education system, strengthen civil society and the role of women and non-Muslims, and to foster inter-faith dialogue.
"Is there any reason why such aid cannot be linked with Pakistan's performance, not only in how it deals with its minorities, but how it proposes to review and revise discriminatory legislation itself?" he said.
In Afghanistan, the bishop said that although girls and women had benefited from international intervention, this had not been the case for Christians.
Despite the constitution incorporating the UN Declaration of Human Rights, Christians in the country do not enjoy freedom of belief or expression.
"The explanation usually given is that sharia will always 'trump' any constitutional guarantees in these areas," he said.
"This must be a matter of huge concern to the taxpayers in this and other countries who are shouldering a massive burden in the belief that they are promoting freedom in Afghanistan."
He said resurgent Islam was the common element in much of the turmoil in the Middle East, North and West Africa, and South Asia.