Technology giants have pledged to join forces in efforts to tackle terrorist content online following a summit with the Home Secretary.

Facebook, Google, Twitter and Microsoft committed to explore options for a cross-industry forum and step up collaboration on technical tools that aim to identify and remove extremist propaganda.

The plans were announced after a meeting between senior executives from the four firms, as well as figures from other companies, and Home Secretary Amber Rudd.

A number of platforms have repeatedly faced calls to do more to stop terror-related videos and pages spreading on the web.

The debate flared up last week after it emerged that information on how to mount an attack was easily accessible in the wake of Westminster terrorist Khalid Masood's murderous rampage.

In a joint statement after the meeting, bosses from Facebook, Google, Twitter and Microsoft said they would "encourage the further development of technical tools to identify and remove terrorist propaganda".

"Companies apply unique content policies and have developed - and continue to develop - techniques appropriate for or unique to their own platforms," they said.

"Nonetheless, there is a significant opportunity to share the knowledge gained in these varied efforts to develop innovative solutions."

The companies will also explore the creation of a new forum to increase collaboration within the industry.

They said: "Companies increasingly share best practices with one another, and we have seen that sharing lessons learned across sectors can improve our collective response to this challenge.

"Each of our companies also commits to urgently improve that collaboration."

The internet giants also outlined two further goals - more support for "younger" companies on how to counter terrorist material online, and to "promote alternative and counter-narratives" through civil society organisations.

"Our companies are committed to making our platforms a hostile space for those who seek to do harm and we have been working on this issue for several years," the statement said.

"We share the Government's commitment to ensuring terrorists do not have a voice online."

Ms Rudd reported that it was a "useful discussion", and welcomed the commitment to set up a cross-industry forum.

The Home Secretary said: "My starting point is pretty straightforward. I don't think that people who want to do us harm should be able to use the internet or social media to do so. I want to make sure we are doing everything we can to stop this.

"In taking forward this work I'd like to see the industry to go further and faster in not only removing online terrorist content but stopping it going up in the first place.

"I'd also like to see more support for smaller and emerging platforms to do this as well, so they can no longer be seen as an alternative shop floor by those who want to do us harm".

The Home Secretary also raised concerns about the issue of encryption and warned that there should be no safe space for terrorists to communicate online.

"I am clear that Government and industry need to work more closely together on this issue so that law enforcement and the intelligence agencies can get access to the data they need to keep us safe," she said.

Further meetings are planned to further address this issue.

A fresh debate over authorities' access to communications was sparked after it was reported that Masood's phone connected with encrypted messaging service WhatsApp shortly before the atrocity.

WhatsApp has said it is "co-operating with law enforcement as they continue their investigations".

Masood killed four people in last week's terror attack. An inquest for Masood, 52 - who was shot dead by police - was opened and adjourned on Thursday.

Liberal Democrat home affairs spokesman Brian Paddick said: "Of course, Internet Service Providers and social media platforms must do everything they can to prevent terrorist material being spread online.

"But I hope the Conservative Government's obsession with undermining our security online has finally been put to bed for good."

Labour MP Yvette Cooper, chairwoman of the Commons Home Affairs Committee, said: "This is all a bit lame. All the Government and social media companies appear to have agreed is to discuss options for a possible forum in order to have more discussions.

"Having meetings about meetings just isn't good enough when there is still illegal terrorist recruitment propaganda up online.

"They need to get on with taking it down, and to say what resources they will put into doing this."