Planned job cuts could undermine the UK's intelligence performance, defence unions have said.

A reduction of 121 posts has been proposed for the Defence Intelligence Staff (DIS) which analyses information from GCHQ, MI6 and the MoD. The DIS provides assessments not just for the Ministry of Defence and the armed forces but the entire UK intelligence community.

The union Prospect responded by saying such cuts "would seriously undermine the quality of assessed intelligence provided to both the MoD and to the UK's central intelligence apparatus".

It added: "Cuts of the size envisaged are likely to mean either that the DIS loses important perspectives to its work or it simply does everything less well.

"Either way greatly increases the chances of an intelligence failure and is likely to lead to less well-informed operational planning, policy-making and procurement decisions."

In a statement, the MoD added: "No decisions have been taken and intelligence capability will not be compromised. Streamlining is not about reducing high-priority defence outputs, it is about achieving those outputs more effectively."