The UK’s financial watchdog is warning banks to review their potential exposure to financial crime in Afghanistan amid fears of resurgent terrorist activity in the country following the withdrawal of foreign troops.

Hours after the last evacuation flight left Kabul airport, the Financial Conduct Authority issued a notice reminding financial firms to guard against money-laundering risks after US military operations were wound down and the Taliban took control of the country.

The FCA said banks and other financial firms were expected to monitor and assess customer transactions with individuals, groups or businesses in Afghanistan to “mitigate the risks [of] their firm being exploited to launder money or finance terrorism”.

Earlier this month, the US’s top military general warned the return of Taliban rule could accelerate the possible threat of terrorist groups regrouping in Afghanistan. Last week, suicide bombings killed more than 140 Afghans as well as 13 US soldiers outside Kabul airport. Islamic State’s affiliate in Afghanistan has claimed responsibility for Thursday’s attack.

The central Asian country is in a state of transition after Joe Biden promised to end 20 years of US military presence in the country by 31 August.

“Developments in Afghanistan have highlighted the continuing need for robust systems and controls that respond to changing risks,” the FCA said in its release.

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“We expect firms to establish and maintain systems and controls to counter the risk they might be used to further financial crime.”

Financial firms were also told to report any suspicious activity to the UK Financial Intelligence Unit and the National Crime Agency, and review existing sanctions already in place in relation to Afghanistan.

The FCA issued similar warnings over financial crime risks in 2015 in regard to banks’ dealings with Ukraine, following Russia’s annexation of Crimea months earlier. At the time, the watchdog urged firms to take extra precautions over any dealings or transactions with the country after the EU launched sanctions and asset freezing orders against members of Ukraine’s former government and individuals who were allegedly threatening Ukraine’s independence.