The Royal Navy Fleet Commander has said the Queen Elizabeth-class aircraft carriers are "necessary" for Britain's "global responsibilities".
Vice Admiral Jerry Kyd said during an online webinar on Monday that the ships are a "symbol of strength".
He said they offer a "well-found sustainable base for delivering influence" and that they are ideal for the "'Global Britain' manifesto of this current Government in the post-Brexit world".
It comes as HMS Queen Elizabeth edges closer to operations after returning to Portsmouth this month as a "fully-trained aircraft carrier".
"Aircraft carriers and maritime air power is not just about metal and ships and aircraft," VAdm Kyd said during the International Institue for Strategic Studies event.
"They are very much more about being a metaphor for a nation state’s attempt to be relevant on the global stage at the strategic level, and that's crucial.
"When aircraft carriers sail, it tends to be noticed."
He added: "An aircraft carrier capability with that combined air maritime cut, is lethal, it’s agile, it’s multi-dimensional, it is survivable and is a symbol of military strength and immediately reassures allies and it deters adversaries.
"If you can do it, why not have it?"
During the conference, VAdm Kyd suggested HMS Queen Elizabeth could be sent to the Far East on her first operational deployment.
Reports suggested the ship would be sent to the South China Sea to counter growing Chinese assertiveness in the region.
WATCH: VAdm Kyd discusses the importance of the aircraft carriers.
China claims almost all of the politically-complicated waters - however, five other governments also claim all or part of the sea.
VAdm Kyd, a former captain of HMS Queen Elizabeth, said the carriers can be used "meaningfully" against a range of new threats, including climate change, as well as "supporting Government's wider foreign policy objectives".
He added "state-based power play is more likely going to be played out sea in the future".
He also defended the carriers, saying "investing in power projection capability at sea, to my mind, makes entire sense".
The Prime Minister's chief adviser has previously been very critical of the Navy's £6.2 billion aircraft carrier programme, calling it a "farce" in a blog post last year.
Dominic Cummings also claimed the ships could not be used against a "serious enemy".
Last week, reports emerged that Mr Cummings is preparing to visit classified military sites ahead of a major foreign, defence and security review, designed to meet "the totality of global opportunities and challenges".
Number 10 told Forces News he "regularly visits Government sites" as part of his role.
Cover image: The Royal Navy's two Queen Elizabeth-class aircraft carriers in Portsmouth (Picture: Royal Navy).