The Government should consider reintroducing national service to protect Britain, the author of the defence review has suggested.

Former Nato chief Lord Robertson said introducing a Swedish-style national service 'should certainly be on the agenda' due to the 'threats that we now face'.

The Labour peer's comments are his latest major intervention in recent weeks after he accused his own Government of 'corrosive complacency' on defence spending.

Last week a House of Lords committee that he chairs heaped pressure on the Government to publish its defence spending plan - which is now more than six months overdue.

Now Lord Robertson, who wrote the Government's strategic defence review last year, has suggested Britain should reintroduce national service as part of an 'all of country approach' to defence.

The former defence secretary appeared in front of the joint Parliamentary committee on the National Security Strategy on Monday. He was asked: 'In Sweden, every resident aged 16 to 70 has a legally defined role in civil resilience. Should we do that?'

Lord Robertson said: 'I think there is a case for that. It might go against the grain in terms of the way in which we think of ourselves.

'But I think given the nature of the threats that we now face, both in a civil as well as a military context, I think there would be a case for putting that forward.

'We talk about a defence readiness bill in our review, which would involve society as a whole. It appears it's not going to be in the King's speech next week or the week after next, which is a pity, because it's a crucial part of part of what we promoted.

'But I think ideas like that should certainly be on the agenda.'

Under the Swedish system, everybody between the ages of 16 and 70 is legally obliged to contribute to the defence of the country in the case of war.

This includes military conscription, civil conscription such as rescue services or maintaining critical national infrastructure, or general national service carrying out tasks decided by the authorities.

National service in Britain - which came into force in January 1949 and required all physically fit men between 17 and 21 to serve in the armed forces for 18 months - was ended in 1960.

Other countries, such as Finland, already have military conscription and in December Germany's parliament voted to introduce voluntary military service following Russia's invasion of Ukraine.

Lord Robertson's latest intervention comes as the Government faces increasing questions about the Armed Forces' readiness to fight a war. Defence Secretary John Healey said last year that Labour would publish the ten-year Defence Investment Plan by last autumn, but this is now not expected until the summer.

Last week the Lords committee that Lord Robertson chairs called on the Government to set a 'clear and costed' path to spending 5 per cent of GDP on defence.

On Monday he called for a 'national conversation' on defence so that Britons are aware of the 'acts of sabotage, cyber-attacks, disinformation campaigns and espionage' that we are already facing from hostile countries such as Russia and Iran.

The Labour peer called out the 'complacency' on defence, adding: 'And it's not just in government. It applies throughout society.'

Lord Robertson said: 'Inside the United Kingdom, I think there is a view that we are safe. We don't notice what is happening elsewhere, and yet it is happening day by day, cyber-attacks and attacks on undersea cables, all of these things are ongoing.'

He added: '[In] the 1930s, we didn't prepare until the crisis was actually on us. It would be horrible to think that it would take an actual crisis, an actual attack on the United Kingdom, before we woke up to the kind of threats that are facing us.'

The Daily Mail is urging increased spending through its Don't Leave Britain Defenceless campaign.