Prince William has vowed to honour his “much-missed grandmother”, Queen Elizabeth, through his environmental work.

The Prince of Wales has given his first speech since the monarch died last month, and in his address to the United for Wildlife Global Summit, he reaffirmed his commitment to the “war” against the illegal wildlife trade while reflecting on the influence his grandparents and father, King Charles, have had on his charitable efforts.

He said: “Our natural world is one of our greatest assets. It is a lesson I learnt from a young age, from my father and grandfather, both committed naturalists in their own right, and also from my much-missed grandmother, who cared so much for the natural world.

“In times of loss, it is a comfort to honour those we miss through the work we do.

“I take great comfort then from the progress we are making to end the illegal wildlife trade.”

The 40-year-old royal blasted those involved with wildlife crime and its impact on the world.

He continued: “There are still too many criminals who believe they can act with impunity, too many lives being destroyed and too many species on the brink of extinction due to this heinous crime.

“[United for Wildlife] set out to ensure that those involved in wildlife crime face an international response as powerful and coordinated as any other serious and organised crime.

“To bring their sinister operations out of the shadows and to ensure that communities are equipped, empowered and supported to protect themselves and their natural world.”

Before delivering his speech, William spoke to ranger Altin Gysman from the Southern Africa Wildlife College, whose colleague Anton Mzimba – who the prince had previously met – was shot dead in front of his family over the summer.

He said: “There is a war going on. Everyone doesn’t really see it”.