Chief executives of two Icelandic pension funds have resigned after being embroiled in the Panama Papers scandal.

Kári Arnór Kárason and Kristjáns Arnar Sigurðssonar, chief executives at the ISK157bn (€1bn) Stapi pension fund and the ISK171bn Sameinaði pension fund, respectively, stepped down following an investigation by RÚV, the Icelandic public broadcaster.

The investigation by news programme Kastljós revealed both were named in the so-called Panama Papers, a cache of millions of documents from Panamanian law firm Mossack Fonseca initially leaked to a German newspaper.

In a brief statement released 27 April, Sigurðssonar said he had decided to resign but claimed he had always acted with integrity and taken care to comply with existing laws and regulations.

In a separate statement, Sameinaði said the fund’s director of operations, Ólafur Haukur Jónsson, would fill the vacancy left by Sigurðssonar’s departure until a permanent replacement could be found.

Kárason offered greater detail in his statement, saying he had notified Stapi’s board of his decision to resign but emphasised that he had not profited from either of the companies he was linked to in the leaked files.

The outgoing Stapi chief executive said one of the companies, based in Luxembourg, was set up in 1999 by Kaupthing Bank, and that he gave the bank’s staff “full and unreserved power of attorney” to conduct its business.

He said he believed the company was eventually wound up, and that its investments proved unsuccessful, and that he was not in possession of any documents relating to its activities.

“Although it is difficult to be sure of events occurring 16, 17 years ago,” Kárason continued, “I am nevertheless fairly certain I never invested any funds in this company and received no payments from it.”

The second company, launched by MP Bank at Kárason’s behest in 2004, was paid an initial fee of ISK305,200 (€3,500), but never went into operation.

“[The investment] was included in tax returns, valued at the amount of start-up cost and amortised three years later, as a total loss,” he added.

“Thus, I earned no gain or yield from these companies, and they bear no relation to tax evasion.”

Kárason said there was “no doubt” he should have informed his superiors at Stapi of both companies’ existence.

“Although the serious nature of the events I have described here is surely a matter of opinion,” he added, “my assessment of the current social discourse with regard to offshore companies and tax havens is that it cannot be regarded as acceptable for a man in my position – that is, in charge of an establishment responsible for managing public pension savings – to have been associated with business operations of this kind.”

Kárason has been with Stapi since its launch in 2006, when Nordurlands Lifeyrissjodur, where he was managing director, merged with a second pension fund.