A former British diplomat warns yesterday’s cyber-attacks that brought two major Ukrainian banks offline were ‘just a little taster’ of what’s to come.

The blitz, which also crashed a number of government websites, was quickly blamed on Russia, as fears over an impending military invasion persist.

It came hours after Moscow announced it was withdrawing some of the 150,000 troops gathered near Ukraine’s border.

Western leaders and NATO remain sceptical and say they are still waiting for evidence of a full-scale de-escalation.

But even if Russia does mean what it says, cyber-attacks will remain a part of President Vladimir Putin’s ‘long game’, warns cybersecurity expert Danny Lopez.

It would be ‘really naïve’ to think such attacks would only be aimed at Ukraine, plus malware will cross borders ‘incredibly fast’ in our interconnected world, he adds.

Having worked as a senior diplomat to the US during the Crimea crisis of 2014, Mr Lopez has learnt a lot about Moscow’s playbook and warns that ‘everything is on the table’.

He tells Metro.co.uk: ‘The majority of UK businesses are not prepared for the ferocity of cyber-warfare that would be unleashed if Putin decided to step up cyber-attacks.

‘Having 150,000 troops by a border is a significant threat, but I cannot overemphasise how brutal a cyber-attack could be too.’

UK infrastructure, banks, travel and power networks are ‘all extremely vulnerable’, Mr Lopez adds, but still many large firms think ‘it won’t happen to us’.

Yesterday saw Privatbank, Oshadbank and a handful of Ukrainian government department websites hit by denial of service attacks – which essentially involve overwhelming a network so it can no longer cope.

‘That multiplied by 10 could bring a country to its knees for a significant amount of time,’ says Mr Lopez, who is now CEO of cybersecurity firm Glasswall.

‘Yesterday was a little taster. You can do that with every bank, utility companies, government departments that offer critical services and infrastructure to people.’

Ukraine has been the victim of Kremlin-backed cyber hackers since Russia annexed Crimea in 2014.

But concerns remain that such attacks could be stepped-up as part of Moscow’s efforts to prevent its neighbour from becoming a NATO member.

‘If we see a de-escalation of the situation on the ground, we are likely to see an escalation of cyber warfare,’ adds Mr Lopez.

Using an army of hackers, he says Russia can have the same sort of impact and make its point to Ukraine without a single gunshot being fired.

‘Anti-virus software and firewalls only protect against known threats. The real risk to the UK is what we call Zero-Day threats,’ he adds.

‘These are new unknown threats. There are no patches for them and they wreak havoc within hours, whilst the security services and technology industry tries to catch up. These are extremely dangerous to Governments as well as businesses.’

The technology to fight these threats is still relatively new, leaving software companies playing catch up right from the start.

‘There’s a lot of stuff that organisations should be thinking about to make sure they are as prepared as they can be,’ says Mr Lopez.

‘Can they do it over the next 48 hours? Of course not. Is it something they should be thinking for the next three, six, nine, 12 months, absolutely.’

Asked how seriously the world should take Russia’s assurances of troops being withdrawn, Mr Lopez says: ‘We’re talking about what’s in Putin’s brain, and no one really knows what that is, he’s very difficult to read, very unpredictable.

‘You can rely on intelligence and satellite imagery of what’s going on at the border with Ukraine and you can work out exactly how many troops are stationed there.

‘But the reality is that the next move is down to what he himself individually is going to decide on the day. For Putin this has always been about the long game and that he has time. Here we are eight years after Crimea.

‘Putin himself has been in power since 1999 and during that time we’ve had five prime ministers, so he is able to play the really long game here and a very different timing when it comes to strategy.

‘The pot is on the stove for a really long time, it’s not necessarily spilling over, but the longer that pot remains on the stove the more he’s able to weaken adversaries and he does play on that unpredictability.’

Mr Lopez believes Putin is ‘intent on avoiding war’ as he recognises the human and economic costs that it will bring, but that doesn’t mean he isn’t prepared to invade.

An alternative to a full-scale war could be some kind of skirmish at the border, which again would show Russia is prepared to follow through with its threats.

In some ways, the diplomatic tensions over the past few weeks have allowed him to test the waters, as the West has now ‘made some pretty clear statements on what it will and won’t do’, he adds.

‘Maybe the NATO conversation now is delayed by 10 years. From a Russian perspective you could argue that the win with a potential withdrawal at this stage is actually quite significant.

‘He doesn’t want to come across to the West as if he was bluffing. He needs to make sure that we all understand that this was never a bluff.

‘I don’t think anyone would really think Putin is bluffing. You know he can go all the way, but then there is a lot to balance there in terms of all the costs that are associated.’

Mr Lopez says Russia has ‘been able to get way more of a reaction of what the West will and won’t do’ but could test its neighbour’s limits more.

‘You could argue that the message that needs to be inflicted on Ukraine is now more important to Putin,’ he adds.

‘I think he has all the answers he needs from the West, whereas with the Ukraine there’s probably a bit more threatening to do.’

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