US whistleblower and privacy activist Edward Snowden has drawn attention to Australia’s new metadata laws, which come into effect today.

Mr Snowden, 32, tweeted this morning to his nearly 1.5 million followers to remind them of the looming legislation.

The anti-surveillance campaigner followed his message with a series of tweets decrying the monitoring of citizens by governments and security agencies.

From today, Australian telecommunications companies and internet service providers will be required to retain the metadata of their customers for two years.

Information which needs to be stored includes identifying details, times, dates and durations of incoming and outgoing phone calls, text messages and emails.

Attorney-General George Brandis has reminded Australian companies they have an “important national security obligation” and demanded they comply.

A former CIA contractor, Mr Snowden is believed to be living in an undisclosed location in Russia after fleeing prosecution in his home country.

He fled the US in June 2013 before leaking thousands of classified National Security Agency documents which revealed the systematic surveillance of the public by government agencies.

He was later charged with a criminal theft offence and two violations of the Espionage Act, each of which carries a maximum 10-year prison sentence.

Mr Snowden joined Twitter on September 30 and announced his arrival with a cheeky jab at the NSA, who accused the whistleblower of damaging US interests with acts tantamount to terrorism.