Britain is delaying the publication of a declaration on internet freedom by the 47 members of Europe's human rights watchdog after objecting to a probe into the gathering of "vast amounts of electronic data" by intelligence agencies.

In a sign of Britain's determination to protect the work of GCHQ and other intelligence agencies, the government is declining to endorse a political declaration by the Council of Europe that could limit the ability of "security agencies" to gather electronic data.

Shami Chakrabarti, the director of Liberty, said that the tactics risked turning Britain into an "arrogant bad boy on the world stage".

Britain intervened during a Council of Europe ministerial conference in Belgrade – Freedom of Expression and Democracy in the Digital Age – where a 14-page document was due to be published on Friday by the 47 members of the body which established the European Convention on Human Rights.

The document, entitled Political Declaration and Resolutions, says that the Council of Europe should examine whether the gathering of data by intelligence agencies is consistent with the European Convention on Human Rights.

The disputed section of the draft declaration says: "We invited the Council of Europe to ... examine closely, in the light of the requirements of the European Convention on Human Rights, the question of gathering vast amounts of electronic communications data on individuals by security agencies, the deliberate building of flaws and 'backdoors' in the security system of the internet or otherwise deliberately weakening encryption systems."

The document has been adopted because no country has a veto. But publication has been delayed while negotiations continue into next week as Britain decides whether to register its concerns in public. It could publish a side letter or demand that a footnote is added to the declaration making clear it does not accept the disputed section.

The intervention suggests that Britain is concerned by the prospect of a Council of Europe investigation into the work of intelligence agencies in areas highlighted by the US whistleblower Edward Snowden. The leaked NSA files show that British and US intelligence agencies have cracked a large proportion of the online encryption that hundreds of millions of people rely on to protect the privacy of their personal data.

A GCHQ document from 2010, published in the Guardian, the New York Times and on the ProPublica website, said: "For the past decade, NSA has lead [sic] an aggressive, multi-pronged effort to break widely used internet encryption technologies. Vast amounts of encrypted internet data, which have up till now been discarded, are now exploitable."

Chakrabarti said: "Bad enough that our authorities engaged in blanket surveillance without democratic mandate or legal authority; worse still when they attacked the ethical journalists who exposed that scandal. Now they delay the Council of Europe's action on the issue and risk turning Britain into an arrogant bad boy on the world stage. The nation that led the establishment of post-war European human rights now jeers at the Strasbourg court and tolerates no scrutiny for spooks or privacy for ordinary people. Churchill must be spinning in his grave."

The Council of Europe, which oversees human rights, was established in 1949 three years after Churchill called for the establishment of such a body as a first step to a United States of Europe in a landmark speech to the University of Zurich in 1946. He said Britain should support the USE but should not join.

He said: "Under and within that world concept, we must re-create the European family in a regional structure called, it may be, the United States of Europe. The first step is to form a Council of Europe.

"If at first all the states of Europe are not willing or able to join the union, we must nevertheless proceed to assemble and combine those who will and those who can. The salvation of the common people of every race and of every land from war or servitude must be established on solid foundations and must be guarded by the readiness of all men and women to die rather than submit to tyranny.

"In all this urgent work, France and Germany must take the lead together. Great Britain, the British Commonwealth of Nations, mighty America, and I trust Soviet Russia – for then indeed all would be well – must be the friends and sponsors of the new Europe and must champion its right to live and shine."

Britain had no objection to other sections in the draft declaration, presented at the meeting in Belgrade this week, which warned that mass surveillance could undermine or destroy democracy and said that the openness of the internet should be preserved.

On the threat to democracy, the declaration said: "Data can be collected and processed for a legitimate aim including the objectives set out in the Council of Europe's Statute. Any data collection or surveillance for the purpose of protection of national security must be done in compliance with existing human rights and rule of law requirements, including Article 8 of the European Convention on Human Rights.

"Given the growing technological capabilities for electronic mass surveillance and the resulting concerns, we emphasise that there must be adequate and effective guarantees against abuse which may undermine or even destroy democracy."

On preserving internet openness, the declaration says: "We renew our commitment to do no harm to the internet and to preserve its universality, integrity and openness. Any measure, including blocking and filtering, that might interfere with people's freedom to access and communication via the internet must be taken in compliance with international human rights law."

The editor of the Guardian, Alan Rusbridger, is to appear before the Commons home affairs select committee next month.

• This article was amended on 9 November 2013 to make clear that the publication of the declaration has been delayed while the UK decides how to register its opposition to the disputed section.