Intelligence chiefs will have to give evidence on key issues in public under Gordon Brown’s proposals for a new national security strategy to be published today.

The Prime Minister wants MI6, MI5 and GCHQ, the signals intelligence centre, to be more transparent and open to scrutiny. Today’s White Paper will include a plan for the security and intelligence services to appear before MPs in Parliament when it is judged to be appropriate.

At present, under a system that has existed for 14 years, the heads of the agencies and other senior officials from MI6, MI5 and GCHQ give evidence in private to the parliamentary Intelligence and Security Committee (ISC). The MPs and peers who serve on the committee have had to operate within “a ring of secrecy”.

Now, Mr Brown wants to introduce reforms to allow better public scrutiny of the way that the ISC works. One proposal that the ISC be converted into a normal select committee, with all hearings before MPs held in public, has been rejected.

However, the national security strategy White Paper is expected to set out a mechanism for holding some of the meetings in public. The intelligence and security agencies have given their support for more public scrutiny on the condition that it does not compromise secret sources or damage opera-tional sensitivities. The head of MI6 is Sir John Scarlett and the head of MI5 is Jonathan Evans.

In a Green Paper published last year, the Government effectively quashed the idea of turning the ISC into a select committee when it said that the parliamentary committee scrutinising the work of the secret agencies needed regular access to “much more highly classified information and evidence than that normally shared with select committees”.

The new-style ISC, which is currently chaired by Margaret Beckett, the former Foreign Secretary, will hold hearings in public wherever possible. An independent investigator, whom the committee can use to check claims made by the secret agencies, is also expected to be appointed.

The ISC was established by the Intelligence Services Act 1994 to examine the policy, administration and expenditure of MI6, MI5 and GCHQ. The ISC also examines the work of the Cabinet Office’s Joint Intelligence Committee, and takes evidence from the Defence Intelligence Staff.

The other members of the ISC include Michael Ancram, the former Tory Cabinet minister, Alan Beith, the veteran Liberal Democrat MP, and Michael Mates, a former Conservative Northern Ireland Minister.

Whitehall sources said that Mr Brown was keen to make the ISC more open, and that the planned reforms followed other moves to strengthen the intelligence structure within the Cabinet Office.

Before his retirement last autumn, Sir Richard Mottram held the dual posts of chairman of the Joint Intelligence Committee and Permanent Secretary for Security, Intelligence and Resilience. These jobs were then split between two officials: Alex Allen took over as chairman of the JIC, and Robert Hannigan became security and intelligence adviser to the Prime Minister.

Times Recommends

• The fourth plinth art project: famous for 60 minutes
• Rubik has a new puzzle to irritate the nation
• Is it Radio 4 or Radio Bore?