Donald Trump has signed a controversial executive order aimed at stepping up deep-sea mining within the US and in international waters. The Thursday order is the latest issued by the US president to try to increase America's access to minerals used by the aerospace, green technology and healthcare sectors. Andrew Peach hears from Gerard Barron, Chairman and CEO, The Metals Company, which has been long pushed for permission to mine in the seabed, and Duncan Currie from Deep Sea Conservation Coalition, which is campaigning against mining in the seabed.