In his first campaign visit of Monday, Rishi Sunak took part in football drills at Chesham United football ground alongside young players.

The Prime Minister tried his hand at dribbling exercises alongside four different age groups: under-eights, under-nines, under-11s and under-16s.

Mr Sunak was later presented with the trophy that Chesham United men’s team won on coming top in the Southern League Premier South, and stood for photos.

The Prime Minister could also be seen talking with teenage volunteers acting as referees on the pitch as he sought to promote his new national service policy.

Rishi Sunak has called a General Election for July 4, and has recently announced a "bold" plan to bring back a form of compulsory national service for 18-year-olds.

Rishi Sunak has defended the plans amid a ministerial backlash and Tory confusion about the policy.

The Prime Minister said the policy, which will see 18-year-olds forced to either sign up to the military or cyber defence force or undertake community volunteering work, would make society “more cohesive” and strengthen the UK’s defence.

But a serving minister complained he was not consulted on the £2.5 billion policy and senior Tories faced questions over whether parents would be liable for fines if their adult children refused to take part.

Under the Tory plan, due to be fully in place by 2029-30 if Mr Sunak wins the election, all 18-year-olds will be legally required to take up either a 12-month placement in the armed forces or cyber defence or give up the equivalent of one weekend a month to volunteer in their communities.

Around 30,000 full-time military placements will be on offer, with the vast majority of 18-year-olds expected to do the compulsory community roles instead, working with organisations such as charities, the NHS, police or fire services.

Mr Sunak told reporters on a campaign visit in Buckinghamshire: “This modern form of national service will mean that young people get the skills and the opportunities that they need which is going to serve them very well in life.

“It’s going to foster a culture of service which is going to be incredibly powerful for making our society more cohesive and in a more uncertain and dangerous world it’s going to strengthen our country’s security and resilience.

“For all these reasons I think this is absolutely the right thing to do. Yes, it is bold, but that’s the kind of leadership I offer.”

But Northern Ireland minister and Wycombe MP Steve Baker publicly criticised the way the policy had been “sprung” on Tory candidates.

He suggested had it been a government policy rather than a Tory proposal, he would have had a say because of the particular sensitives around military service in Northern Ireland.

“But this proposal was developed by a political adviser or advisers and sprung on candidates, some of whom are relevant ministers,” he said.

In a sign of wider unease at the policy, he added: “History has proven time and time again that liberty under law – not compulsion and planning – is the surest road to peace and prosperity.”

Broadcast interviews by senior Tories also demonstrated that key points of the policy were yet to be worked out, with a royal commission promised to develop the details.

Ministers compared it to the requirement for children to be in education or training up until the age of 18, which can leave parents liable for fines if their children do not show up to school.