The Government is wrong to ask the Foreign Office to make savings of up to 40 per cent of its budget within the next five years, a committee of MPs has said. The Foreign Affairs Committee has called for the human rights agenda to become a top priority again.

The Foreign Office, whose current budget of £1.7 billion is already smaller than most other departments, has been asked to plan for savings of between 25 and 40 per cent in preparation for the 2015 Spending Review.

Big savings were made by the Foreign Office under the 2010 Spending Review, and most of these were achieved by cuttings its grant to the BBC World Service.

A similar cut to the British Council budget under this review, would weaken the UK's ability "to project soft power and culture" in countries with human rights concerns, such as Russia and the Gulf, the committee warns.

Nor is the Foreign Office well placed to make back-office savings, with ageing IT systems that need replacement and security requirements that mean it cannot share payroll and human resources with the rest of Government.

The committee called for human rights needs to become top priority again. The MPs on the committee were concerned that Sir Simon McDonald, Permanent Under-Secretary at the Foreign Office, admitted human rights was now not a top priority and that "in a constrained environment", other affairs had "supplanted it to an extent."

The committee said: "We believe this to be a consequence of the savings imposed so far on the department."

The committee lamented that the two larger-spending departments will be protected in the Spending Review while the Foreign Office, which already spends a fraction of what they do, "is to be exposed to the full force of Spending Review cuts."

They claim this is a risk to national security. "As far as our national security is concerned, it is beyond irresponsible to treat FCO expenditure as the only unprotected department in this group."

The committee says the country needs a properly resource foreign service. "Over the last Parliament the country was found to be lacking in expertise, analytical capability and language skills to manage the fallout from the Arab Spring and the crisis in Ukraine. In 2010 it might have been thought that expertise on Benghazi, Donetsk, or Raqqa was surplus to requirement. These have become vital areas for our national security, evidencing the real dangers of an under-funded Foreign and Commonwealth Office."

Committee chairman Crispin Blunt was quoted by Politics Home as saying: "In short, we cannot recall a more complex and challenging policy-making environment in recent decades, and the FCO needs to have the diplomatic and analytical capability to re-assert its leading role in foreign policy-making."

Chancellor George Osborne will announce departmental budgets during the Comprehensive Spending Review on 25 November.