Facebook said on Tuesday it was tightening rules around its livestreaming feature ahead of a meeting of world leaders aimed at curbing online violence in the aftermath of the Christchurch massacre.

A lone gunman killed 51 people at two mosques in Christchurch on March 15 while livestreaming the attacks on Facebook. It was New Zealand's worst peacetime shooting and spurred calls for tech companies to do more to combat extremism on their services.

Facebook said in a statement it was introducing a "one-strike" policy for use of Facebook Live, temporarily restricting access for people who have faced disciplinary action for breaking the company's most serious rules anywhere on its site.

First-time offenders will be suspended from using Live for set periods of time, the company said. It is also broadening the range of offences that will qualify for one-strike suspensions.

Facebook did not specify which offences were eligible for the one-strike policy or how long suspensions would last, but a spokeswoman said it would not have been possible for the shooter to use Live on his account under the new rules.