Russian state communications regulator Roskomnadzor said Friday that U.S. social network Twitter was complying with its demand to remove content banned in Russia, but that it was still taking too long to do so.

It said Twitter had removed 60% of such content since Moscow slowed the speed of its service in March to press its demand, but that more than 1,000 illegal materials remained accessible, down from more than 3,000 earlier this year.

Russia this month extended the punitive slowdown until May 15, while acknowledging that the U.S. social media company had accelerated the deletion of content.

Roskomnadzor said it had identified more than 900 new cases of banned content since the slowdown began on March 10.

It said that on average Twitter was removing newly detected illegal content within 81 hours of receiving a request. That is still much longer than the 24 hours demanded in law.

Roskomnadzor says it wants Twitter to delete content that contains child pornography, drug abuse information or calls for minors to commit suicide.

Twitter has repeatedly denied allowing its platform to be used to promote illegal behavior, says its has a zero-tolerance policy for child sexual exploitation, and prohibits the promotion of suicide or self-harm.

"We had a constructive conversation with Roskomnadzor on Thursday April 1 and again on Wednesday April 28," a Twitter spokesperson said Friday. "These were productive discussions about how we can both work to ensure that reports of such illegal content are dealt with expeditiously."

In the April 28 meeting, Roskomnadzor said it and Twitter agreed to establish a direct line of communication between the watchdog and Twitter's moderation service.