The Foreign and Commonwealth Office and Westminster Cathedral are among those that will be taking part in #RedWednesday.
The campaign was organised by Catholic charity Aid to the Church in Need (ACN). To mark the occasion, a candlelit 15 minute Cross procession will leave Parliament Square in the evening at arrive at Westminster Cathedral in time for a liturgy.
Rehman Chishti, the Prime Minister's Special Envoy for Freedom of Religion or Belief, will be leading the procession before speaking at the liturgy.
ACN said this year's #RedWednesday comes at the end of a year where the issue of religious freedom been taken increasingly seriously.
The findings of the Bishop of Truro's Review into the Foreign and Commonwealth Office support for persecuted Christians found that 80 per cent of religiously motivated attacks in the world are against Christians and that this should now be called 'Christophobia'.
Patricia Hatton from ACN (UK), explained that the procession shows solidarity to persecuted Christians – the world's "most widely targeted" faith group according to Pew Research Centre.
She said: "Following the endorsement of #RedWednesday in the Bishop of Truro's review into FCO support for persecuted Christians – commissioned by former Foreign Secretary Jeremy Hunt – the procession is a real chance for Christians to stand together and in a very visible way, show that the lives of Christians and other persecuted minorities matter.
"We urge individuals and groups to come along – to add your voice to the call to stop the persecution of Christians and other faith groups."
ACN highlighted that Christianity in the Middle East is at a point of near extinction. Before 2003, there were 1.5 million Christians in Iraq. Today there are 150,000 with some reports putting it as low as 120,000 following the persecution of minorities by jihadists.
The charity added: "At the same time, Islamist extremism has extended its reach to Sri Lanka and Philippines; India's government under Prime Minister Modi grows increasingly populist and nationalist; North Korea and China continue to persecute Christians ruthlessly."
Across the UK, 13 cathedrals will be turning red, including St Chad's in Birmingham, St Mary's in Edinburgh and Amargh Cathedral. This in addition to the parishes and schools that will be going red to stand up for faith and freedom.
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