Greenpeace International lost €3.8m - just over £3m - as the result of a currency exchange contract after a staff member gambled on currency markets.

The organisation has released a statement offering a full apology to supporters and donors and the international board has terminated the contract of the member of staff responsible.

Greenpeace International blamed the losses on a “serious error of judgement by an employee in our international finance unit”, who acted without authority and entered into contracts to buy foreign currency at a fixed exchange rate while the Euro was getting stronger, meaning that it lost out on €3.8m against a range of other currencies.

The statement adds that there “is no evidence of personal gain” for the member of staff involved and that he has been “relieved of his position”.

Greenpeace International’s annual report for 2013, which will be published soon, will show a deficit of €6.8m, including the currency exchange losses. Its income for 2013 was €72.9m.

The organisation said that frontline campaigning will not be affected by the shortfall and that it will adjust spending in infrastructure investment to make up for the loss.