The government’s new cyber security strategy has caused controversy in Parliament within hours of its launch earlier today.

New Speaker John Bercow had to order the government to send Home Office minister David Hanson to the House of Commons to answer an emergency question put down by the Conservatives.

The opposition is angry that details of such an important plan were leaked before its announcement to MPs.

Tory shadow home affairs minister Crispin Blunt said allowing the announcement to be leaked outside Parliament was "not only disgraceful, more alarmingly it is shambolic when the ministers directing this strategy who are supposed to keep us safe cannot even manage the orderly public release of new policy."

Liberal Democrat spokesman Tom Brake said the proposals could impact civil liberties, and demanded an assurance the new Cyber Security Operations Centre would not snoop on ordinary citizens' use of the internet.

"MPs will be concerned that there was a leak about of all things cyber security strategy," he said.

In response, Hanson said prime minister Gordon Brown had made a written statement spelling out the detailed proposals and "acted entirely properly".

He denied there had been briefings to the press in advance of the announcement and claimed the proposals would defend citizens from cyber crime and threats to security.

The minister said the mistaken issuing of a D-Notice concerning security without imposing an embargo had allowed some information to leak. A D-Notice is an official request to editors not to publish certain information on the grounds of national security.