Political leaders deserve praise for their mantra to “build back better”. The pre-pandemic world suffered from deep flaws. It is good if leaders are determined to improve on the status quo ante, and we should hold them to it. But the range of things we need to rebuild better is so vast that there is a risk of a bandwidth problem, where politicians choose to focus on some to the detriment of others.

One policy area that has — belatedly — been receiving more attention is the need to combat illicit financial flows. Yet it remains overshadowed by the challenges of post-pandemic recovery, fairer economic settlements nationally and globally, and climate change. Leaders and voters could be tempted to think cleaner finance would be a nice-to-have that will nevertheless have to be deprioritised until more urgent tasks have been addressed.

But these are not alternative goals. Given the price tag of the pandemic itself, and of investing in fair recoveries and carbon transitions when it is over, addressing illicit finance is more urgent than ever. On Thursday the UN’s high-level panel on financial integrity issued a hard-hitting report that laid bare the enormous cost to public finances and economic efficiency from illicit financial flows, ranging from legal but aggressive tax avoidance to money laundering and bribery. Just one egregious example: tax evasion loses Lebanon’s government revenue worth 10 per cent of national income a year.

According to the report, the world’s governments lose more than half a trillion dollars annually to tax manoeuvres that circumvent the intentions of legislatures by exploiting loopholes and discrepancies in the law. As for blatant illegality, criminals launder more than $2tn every year. Bribes amount to $1.5tn to $2tn globally. And the harm to economic efficiency caused by such illegality is likely to be much greater than the ill-gotten gains themselves.

For comparison, the cost of Covid-19 vaccines for all adults in the world would be in the tens or low hundreds of billions. Fighting for global financial integrity is not a distraction from other goals, but a means to achieve them.

That is not all. Corruption or theft can be the deliberate purpose of what is aptly called “corrosive capital”. Another new report, just published by the Center for American Progress, highlights how secretive capital flows have become a tool of malign foreign policy, in particular through influence operations by authoritarian governments targeting democratic societies.

Both reports are ambitious, but in a realistic way, about what can be done. Key to combating corrupt and corrosive finance is ending the secrecy that favours it. The UN panel calls for all countries to have central registries, ideally public, of beneficial ownership information for “all legal vehicles”. That would include trusts, which too often are exempted even by jurisdictions with transparent company ownership. CAP highlights the need to verify and share such information more efficiently, including with law enforcement agencies.

Both reports are commendably lucid about the need to crack down on the enablers of illicit flows — the ecosystems of lawyers, accountants and public relations agents that thrive on helping criminals and tax dodgers.

As the UN report points out, the loophole-riddled system for cross-border corporate taxation must be overhauled. By encouraging legal tax avoidance, existing rules also create incentives for the secrecy and complexity that facilitate outright criminal flows. The panel goes further than what is currently being negotiated at the OECD, calling for multinationals to be taxed on global group profits at a high rate. It also wants country-by-country financial disclosures by all multinationals. It is right on both counts.

Political support for such reforms is increasing. A bipartisan congressional vote has banned anonymous US shell companies. EU ministers just agreed stronger country-by-country reporting. CAP’s call for a “global kleptocracy initiative” is backed by the foreign affairs committee chairs of Congress and the European and UK parliaments. One may also hope that investors will see the benefit of transparency and a level playing field for tax.

But fundamental change requires political will from leaders of the world’s most powerful countries. The G7 and G20 forums should lift financial integrity higher up on their agenda. Particular responsibility lies with the US and UK, both are hosts to large enabling environments for illicit finance, and both vulnerable to corrosive capital. Financial integrity is a global public good. It is an excellent example of where charity can begin at home.