The home security service MI5 is to expand by 50% in response to the terror threat to the UK, the BBC has learned.
Details of the positions have been posted on MI5's website
The home secretary will announce plans to recruit another 1,000 staff in parliament next week.
It will take several years to find and vet the staff, principally to carry out surveillance and intelligence work.
Opposition parties welcomed the news, though a Conservative Party spokesman said the expansion was overdue.
Previously focused largely on Cold War and IRA suspects, the move highlights MI5's shift to recruit many more Arabic speakers and focus on the threat from al-Qaeda.
Surveillance officer job requirements
Able to blend in, average height, build and appearance
Able to remain alert during periods of inactivity
Flexible and able to cope with frequent disruption
The increase will bring MI5 back up to World War II staffing levels.
The agency believes there are thousands of young people moving in and out of Britain with links to groups close to the terrorist network.
MI5 has been criticised in the past for failing to penetrate radical Islamic groups.
Home Secretary David Blunkett is to make the announcement in the House of Commons during next week's debate on controversial terrorism laws introduced after 11 September 2001.
He will be trying to persuade MPs to renew the legislation allowing foreign terror suspects to be detained without trial.
Linguist job requirements
Mother tongue knowledge or honours degree equivalent in required language
British by birth or naturalisation with close links to the UK
Good hearing (to be tested)
Bruce George, chairman of the Commons defence select committee, told the BBC the move was "absolutely necessary".
He said the terrorism threat was increasing, and the committee had been pushing for such an expansion for some time.
'Big brother' state
But the Labour MP warned that people might be concerned about a "big brother" state.
"We need to protect ourselves without alarming people that we have reached 1984 in 2004," he said.
"Enhancing security and policing and civil preparedness without intimidating our own citizens is a delicate task which has to be handled very carefully."
Tory homeland security spokesman Patrick Mercer said the government should have acted earlier.
"I am delighted with what the government have done but why on earth has it taken them so long?" he said.
"We have been asking for extra resources for the intelligence agencies for over two years now. I'm glad that the government has finally listened."
Liberal Democrat home affairs spokesman Mark Oaten said increasing MI5's capacity "made sense".
He added: "Getting better intelligence on, and surveillance of, suspects is a better approach than Blunkett's suggestion of lowering the burden of proof and his plans to continue to hold suspects without charge."
MI5 currently employs around 1,900 people, with graduates starting on a salary of £20,100 a year.
The details of the new positions have already been posted on the agency's website.
Recruits would have to undergo a 60-day intensive training and assessment period, with no guarantee of a job at the end of it.
MI5, which was founded in 1909, has recently embarked on a campaign to recruit more widely, as only 4% of staff are black or Asian.