David Cameron is to warn that the west is not learning the lesson of Russia’s invasion of Ukraine, that authoritarian adversaries will only be spurred on if the west shows hesitation or caution. The foreign secretary will call for the west to be tougher and more assertive and realise it is locked in a battle of wills in which “we all must prove our adversaries wrong – Britain, and our allies and partners around the world”. In his first set-piece speech as foreign secretary outside parliament and after a whirlwind six months in the job, Cameron will argue not enough allies have stepped up to the challenge of a more hard-edged world, whether by increasing defence spending, facing down Iranian proxy forces or championing women’s rights in the Islamic world. He will say: “We need to adopt a harder edge for a tougher world. If Putin’s illegal invasion teaches us anything, it must be that doing too little, too late, only spurs an aggressor on. I see too many examples in this job of this lesson not having been learned.” He will cite the example of the Houthi attacks on freedom of navigation in the Red Sea, pointing out only two countries – the UK and the US – have taken action even though multiple ships have been attacked. “While many countries have criticised the Houthi attacks, it is only the US and Britain that have been willing and able to step up and strike back at them,” he will say. Other countries have joined the Operation Prosperity Guardian alliance, spearheaded by the US in response to the Red Sea attacks, but not in the same active military offensive way as the US and UK. EU countries have formed a separate alliance, Eunavfor Aspides, that is restricted to defending commercial shipping from Houthi attacks and has no mandate to launch assaults on Houthi missile sites inside Yemen. Cameron will also urge all Nato members to be on track to spend 2% of GDP on defence by the time of the alliance’s summit in Washington in July. He will say that some in Europe still “seem unwilling to invest, even as war rages on our continent”. He will say the urgent task is not just to reach the 2% target all Nato countries endorsed at a summit in Newport in 2014, but also to move to establish 2.5% as the new benchmark. Countries still well below the 2% target include Spain, Belgium and Canada. Cameron will also accuse some countries of being cowed by accusations of colonialism and holding back on women’s rights, pointing to the example of countries ignoring calls by survivors of female genital mutilation for the practice to be eliminated. He will say this kind of hesitation “cannot go on. We need to be tougher and more assertive. “We need to out-compete, out-cooperate and out-innovate.” There is little in the extracts of the speech to suggest Cameron believes the UK should soft-pedal on its values in a bid to woo the global south. Instead, he will claim Britain’s departure from the EU, something he strongly opposed as prime minister, provides a freedom to invest in alliances such as Aukus with the US and Australia. He will also claim there is a chance for the UK to weaken Russia’s grip in central Asia, saying it may be possible to strengthen bilateral relations with countries who “see the destructive, reactionary policies of our adversaries as a threat to their security and prosperity”. Cameron’s critics say he has given the appearance of a risk-taking foreign secretary without actually doing anything that shifts the UK outside its familiar role of aspiring to be the favoured private adviser to American policymakers, in return for acting as their public advocates.