The head of the Royal Navy has urged nations not to ignore China amid Russia's invasion of Ukraine, saying: "Focusing solely on the Russian bear risks missing the tiger."
In a speech addressing maritime geostrategy challenges at the Naval and Military Club in London, First Sea Lord Admiral Sir Ben Key underlined the "long-term challenge" of China.
He said: "For while we see Russia as the clear and present danger, China is posing the long-term challenge," he said.
"We find ourselves in a time when the geopolitical landscape is changing before our eyes.
"We're seeing increased state-on-state tensions and transnational issues like the pandemic and climate change which are driving us to adapt."
During his speech to the Council on Geostrategy, the First Sea Lord covered the impact of the conflict in Ukraine, how it affects the Royal Navy's strategy, and the need to look at the wider picture, especially regarding China.
"According to the World Bank, China's GDP is already 10 times that of Russia's. Last year China spent $293bn on defence, growing their defence budget for the 27th consecutive year, whilst Russia spent $66bn, less than a quarter.
"And let's not forget Russian defence investment is only predicted to drop, as the western market for their oil dries up and China buys it on the cheap," he added.
The First Sea Lord "would posit that China is indeed one of the great beneficiaries of this conflict" and highlighted that "if the west is learning lessons from Ukraine, we should be in no doubt so is the Chinese Communist Party".
"Having potentially overestimated some of Moscow's military capabilities, we must be wary of underestimating those of Beijing."
Watch: China shows further signs of ambition to be a major maritime power.
Sir Ben said: "We are seeing the Chinese develop perhaps the world's largest navy in terms of pure hull numbers, coupled with a massive Coastguard and maritime militia."
With the UK in the past doing the same, Sir Ben acknowledged that "at one level, it is arguable that the Chinese are quite entitled to do what they are doing".
However, he did question "if as they claim and regularly repeat that this is about a commitment to peace and prosperity, why would they feel the need to do this, and behave as they are in the South China Sea?"
"Why are they seeking the sort of diplomatic and trade relations bilaterally with a number of nations in the fashion that they are?"
Sir Ben suggested that China will be currently seeing and learning about the strength and unity of the international community.
He went on: "As the Foreign Secretary remarked two weeks ago, we need to learn the lessons of Ukraine and the importance of deterring aggression and apply them to protecting "peace and stability in the Taiwan Strait."
"Deterrence is expensive but it is ultimately cheaper than conflict."
Watch: West needs to 'wake up' to threat of Russia-China alliance, Ellwood says.
The First Sea Lord said that the conflict in Ukraine "offers a number of lessons for us".
"By trying to choke Ukraine's access to the sea, Russia is restricting the Ukrainians' ability to trade and exercise their rights of free and open access. The world is being held ransom to a maritime blockade. It is that stark."
He highlighted that "the world has woken" up to the risks that Russia's invasion poses.
"We are charged to grow"
The First Sea Lord also spoke on the future of the Maritime as he is "determined that we (the Navy) strive to retain the trust of the nation".
"We find ourselves at a moment that none of my First Sea Lord predecessors has enjoyed since the end of the Second World War."
Sir Ben added: "We are charged to grow. We have a degree of change set upon the service, a scale of which proportionately we have not had for 18 years.
"We must deliver on the Government's really significant investment in our ambitious shipbuilding programme: Type 31, Type 32 and Type 26 frigates, the future support shipping and with the Dreadnought-class submarine, the new generation of continuous at sea deterrent.
"All of which must be brought into service over the next 10 to 15 years without dropping a single operational fall," he added.