A group of bishops have warned Prime Minister Tony Blair that the possession of Trident nuclear weapons is "evil" and "profoundly anti-God".
The bishops say the end use of Trident is "evil"
In a letter published in The Independent, the 20 bishops said Trident was "evil" and that "possession and use are profoundly anti-God acts."
The money would be better spent helping developing countries, they say.
Chancellor Gordon Brown has already supported the replacement of the ageing Trident nuclear submarine deterrent.
In the letter the bishops say: "Trident and other nuclear arsenals threaten long-term and fatal damage to the global environment and its people.
"Nuclear weapons are a direct denial of the Christian concept of peace and reconciliation, which are social and economic as well as physical and spiritual.
"The costs involved in the maintenance and replacement of Trident could be used to address pressing environmental concerns, the causes of terrorism, poverty and debt and enable humanity and dignity to be the right of all, and would go a long way towards helping Make Poverty History."
The Trident missile system and the Vanguard submarines which carry them need replacing by 2024 and a decision is set to be taken in the next year.
Estimates of the cost vary from £10bn to £25bn, depending on what type of new missiles or submarines are chosen.
The bishops' letter also says there are "practical, moral and economic objections to the basic concept of having a deterrent".
Downing Street has promised a White Paper on the Trident issue but refused to commit to holding a Commons vote.
Ministers have not ruled out replacing Trident with an air or land-launched system, although most experts believe that they will continue to opt for a submarine-based system.
Signatories of the letter included the Rt Rev Peter Price, Bishop of Bath and Wells; the Rt Rev Colin Bennetts, Bishop of Coventry; the Rt Rev Michael Hill, Bishop of Bristol; the Rt Rev John Saxbee, Bishop of Lincoln; the Rt Rev Timothy Stevens, Bishop of Leicester; the Rt Rev Jack Nicholls, Bishop of Sheffield, and the Rt Rev Dr David James, Bishop of Bradford.