Canada's largest lender has reportedly taken action following a review of its accounts connected to last year's Panama Papers leak, which sparked worldwide controversy and probes into how politicians and business leaders channelled billions of dollars through offshore accounts using some of the world's largest banks.

Royal Bank of Canada closed around 40 clients' accounts and boosted its tax compliance measures following a review of offshore accounts linked to last year's “Panama Papers” scandal. 

Canada's largest lender last year established a team to sift through four decades of internal records to investigate what ties it had to Mossack Fonseca, the Panamanian law firm that found itself at the epicenter of a leak of more than 11 million documents. The leaked data sparked a worldwide scandal and probes into how politicians and business leaders channelled billions of dollars through offshore accounts using some of the world's largest banks.

The Toronto-headquartered firm was among several firms mentioned, along with HSBC and UBS, in the records. 

“The review is completed,” JF Courville, chief operating officer of RBC's wealth management unit, said in an interview with Bloomberg. “We found out we have a business with good controls, but opportunities to improve consistency through constant training to make sure we have consistent interpretation and application of strict policies and procedures.”

He continued: “We reviewed all accounts related to Mossack Fonseca in depth. The relationships with Mossack Fonseca - basically relationships initiated by the client using that law firm as an advisor - represented an extraordinarily small proportion of our total client base.” 

RBC closed certain accounts because they no longer fell within its risk-tolerance remit, Courville said. The shuttered accounts represented less than 0.001 per cent of the group's client base, he said. 

The bank will also this year introduce measures to enhance account agreements with cross-border customers around tax requirements in their native countries. 

“We are also going to continue enhancing the due diligence that we do on clients when operating in countries where automatic transfer of tax information doesn’t exist, including requesting confirmation that they’re filing their taxes on these accounts," Courville said. 

RBC Wealth Management confirmed the accuracy of the report to Family Wealth Report.