David Cameron said he would "make no apology" for having and maintaining security services because of the work they do to keep the country safe.
"I will criticise those who make public the work that they do," he added.
More top news
Orlando Bloom has visited children whose school was destroyed by shellfire during the conflict in Ukraine.
Jeremy Corbyn has launched a fresh attack on "ideological" Conservative cuts ahead of Thursday's elections.
Daddy Day Care star Eddie Murphy is celebrating the birth of his ninth child.