Wellington  - New Zealand Prime Minister John Key bowed Monday to calls to examine procedures of the country's top security agency after it was revealed that it had spied on opposition Green Party legislator Keith Locke.

Locke, a well-known left-winger whose parents were openly members of the Communist Party, said his Security Intelligence Service (SIS) personal file showed that spies had watched him from the age of 11 and continued to do so after he was elected as a member of parliament in 1999.

After initially rejecting demands to review the SIS, Key told reporters he had asked the agency's watchdog, retired judge Paul Neazor, to check that it was "acting appropriately" in maintaining its files on citizens.

Key said he was not instigating a full review of the SIS by Judge Neazor, who is the Inspector-General of Intelligence and Security, but added, "I think it's important for the confidence of everybody to understand what's gone on here."

Locke, who was given his file after he applied formally for it under the Privacy Act, said, "Monitoring a sitting member of parliament, purely because of the views he espouses, is an affront to our parliamentary system.

"It is outrageous that the SIS kept my personal file going after I became an MP even though none of the file documents from 1955 show any intention to break the law or conspire with a foreign enemy.

"It was all about monitoring my legitimate political activities - commonly in antiwar groups and those concerned with international human rights."

Key, who is responsible for the SIS, told Radio New Zealand that the agency should be able to spy on anyone they deemed a risk, whether they were an MP or not.

He said Locke had not been spied on as an MP, but it was possible that things like newspaper clippings may have been added to his file. "Obviously it's a file that's been there for long period of time and I suspect there has been a slightly overzealous staff member that has been adding to that file over time."

An SIS spokesman told a newspaper over the weekend that it was "not actively investigating any current members of parliament."

The Green Party's co-leader Jeanette Fitzsimons, who is also in parliament and has long been outspoken on environment issues, said she would request her own file to see if she had been spied on.

"MPs are elected by the people of New Zealand to hold the government to account and for them to be treated as enemies of the state and spied on by the SIS is absurd," she said. (dpa)