More than 16,000 children have made the deadly Mediterranean journey in search of safety and opportunity in Europe – many escaping conflict, poverty and persecution – since the start of the year. Hundreds have died while trying to cross the sea on wooden boats and inflatable rafts.

Those making this journey include vulnerable and often unaccompanied children who are left with no other choice but to risk their lives.

Unicef believes that if we are to uphold our commitment to protecting children around the world, governments must provide legal routes to prevent children from embarking on this deadliest of migration routes.

The recent House of Lords' EU External Affairs Sub-Committee report showed us that while the humanitarian efforts of Operation Sophia have paid off, the number of journeys being made are not declining and attempts to disrupt the business of smugglers has failed.

The Committee found that to stop the smugglers we need to address the underlying need for these dangerous journeys and it is clear that a lack of safe and legal routes plays a major part in this.

One simple thing we can do is change the UK's own family reunion rules to ensure children are able to reunite with family in the UK by submitting applications from their country of origin, rather than first having to risk their lives to reach Europe and begin this process from there.

It is even more important for us to make this change in light of Brexit which could see Britain leave Dublin III – the EU agreement that unaccompanied children in Europe are currently reliant on to be reunited with family members in the UK. In the absence of this, children will having nothing to depend on aside from the UK's own rules, but these rules are broken.

They only provide a right for children to be reunited with their parents who have been granted refugee or humanitarian status, with no consideration for the all too frequent case of children without the protection of their parents due to the perils of war.

What makes far more sense, and what children really need from us, is an extension of these rules which should provide a right for them to be reunited with extended family members who are willing to care for them in the UK – adult siblings, grandparents, aunts, uncles as well as parents.

This simple change can make a huge difference, not only stopping the deadly journey but also stopping children placing their lives into the hands of smugglers and traffickers to reach Europe in the first place. As well as the journey itself, every step towards the journey is a risk.

In 2016, more than 25,800 unaccompanied children relied on smugglers to reach Italy. In the arms of smugglers children face violence, abuse and exploitation, with many even being sold into slavery or forced prostitution.

The scale of this problem is unimaginable, but a simple solution is right in front of us. If we're serious about continuing to be a Global Britain, then fulfilling our obligation to vulnerable children with a link to the UK is the first step. Our family reunion system should work better for children, not worse, after Brexit .

Though families have been torn apart by war and persecution, we have an opportunity to bring the ones that remain back together without having to face unthinkable and often fatal journeys at sea.