Keir Starmer's delay in tackling online child sex abuse images has left thousands of youngsters vulnerable to paedophiles, campaigners warned last night.The Prime Minister announced tech companies will be forced to stop children viewing or sharing nude images online, amid growing concern over horrific abuse.But the plans gathered dust for more than a year before being finally unveiled on Monday. The PM is now facing accusations of 'cowardice' over his failure to act sooner.Since the proposals were first submitted to Downing Street, the National Crime Agency (NCA) has received tens of thousands of referrals of online child sexual abuse.Officials confirmed the National Centre for Missing and Exploited Children – based in the US, where companies are compelled by law to report suspected cases – refers 1,700 cases a week to the UK's NCA regarding children abused online.That equated to one every six minutes and was 'just the tip of the iceberg', sources said. An NCA spokesman said that each month the referrals lead to 1,200 children being 'safeguarded' from abuse, and 1,000 arrests.The scale of the sickening online abuse has fuelled criticism over the delays, amid reports the Government is also due to unveil a watered-down social media ban for under-16s. Campaigners have warned Keir Starmer's delay in tackling online child sex abuse images has left thousands of youngsters vulnerable to paedophilesShadow home secretary Chris Philp said: 'Keir Starmer has delayed acting for months, even ordering his MPs to vote down Conservative plans to ban social media for under-16s.'While he dawdled, thousands of British children have been endangered online, including grooming for sexual abuse.'Starmer's cowardice, weakness and his desire to suck up to big tech has put our children at risk.'Starmer should apologise for the thousands of children he has endangered and immediately ban social media for under-16s.'Former Home Office minister Jess Phillips, who was responsible for devising the new policy before she resigned last month, has blasted Sir Keir's lack of action.In her resignation letter she said: 'Over a year ago I presented solutions, long worked on by brilliant civil servants, that would end the ability for children in the UK to take naked images of themselves. It has taken me a year to get you to agree to even threaten to legislate in this space.'Not legislate, just threaten.'This is the definition of incremental change. Nothing bold about it... How many children were left without a safety net in the time we dilly dallied and worried about tech bosses?' Former Home Office minister Jess Phillips blasted Sir Keir's lack of actionLast night she said she stood by her earlier criticism and told Sky News the Government's hesitancy 'came from a sort of squeamishness to sometimes take on big tech'.But she also felt 'relief' that Sir Keir had now pledged action. One online safety expert said last night: 'It's unknowable just how damaging this delay has been, but thousands of kids will have been exposed to sexual abuse and other horrific outcomes in the time it's taken to get to this point. That could have been prevented with more speedy action.'Announcing the plans in Olympia, west London, on Monday, the PM said: 'When it comes to the safety of our children, standing by is not an option. 'That is why I'm making sure Britain is the first country in the world to make it impossible for children to take, share or view nude images.'Apple, Google and other tech firms will be given three months to voluntarily introduce the measures or face being forced to do so by law. Companies could then face fines or criminal convictions for their executives, including jail sentences, if they ignore new laws.Tech companies will be required to introduce age verification on smartphones, computers and tablets. Unless someone has been verified as over 18, the device cameras would be unable to capture nude images or display them.The restrictions would apply to new devices and those already sold, with changes introduced through software updates.