Twitter is "making a mockery" of privacy laws, Culture Secretary Jeremy Hunt has said as he pledged to examine how best to bring regulations up to date.
He said it was "crazy" that information which was not allowed to be printed in newspapers was widely available via the microblogging site and other internet sources.
One Twitter user set up an account claiming to expose celebrities who have obtained injunctions to prevent media reporting of their private lives.
It attracted thousands of followers and the contents were widely discussed online amid growing disquiet about celebrities' use of injunctions to prevent stories emerging.
Special focus has been given to the granting of so-called "super-injunctions" whose very existence cannot be reported.
"We are in this crazy situation where information is available freely online which you are not able to print in newspapers," Mr Hunt told journalists at a Westminster lunch.
"Technology, and Twitter in particular, is making a mockery of the privacy laws that we have and we do need to think about the regulatory environment that we have.
"Whatever the law tries to do on privacy, the internet is a very powerful force that you can't buck so we do need to look at it."
Mr Hunt said he would sit down with Justice Secretary Ken Clarke to "see what can be done" about super-injunctions and the wider question of privacy.
Passing a new privacy law would be a massive parliamentary undertaking and it was important to examine the alternatives, he said.