AMSTERDAM (Reuters) - Dutch bank Rabobank expects a fine over its alleged role in the manipulation of benchmark interest rates, which one source said would be around $1 billion (S$1.23 billion) in the next two weeks.

That would make the Rabobank settlement the fifth Libor-related penalty and the second-biggest in a global investigation.

"Various authorities have almost completed their investigation into Rabobank's role in the Libor and Euribor setting process," Rabobank, a cooperative bank, said in a statement.

"Rabobank expects to be able to enter into settlements with these authorities within the next two weeks. Rabobank is not yet in a position to comment on possible settlement amounts." A source familiar with negotiations between the bank and US, UK and Dutch authorities said the level of the fine being discussed was around $1 billion.

Britain's Financial Conduct Authority, the Dutch central bank and the US Commodity Futures Trading Commission declined to comment. The US Department of Justice did not immediately respond to a request for comment.

US and British authorities have already fined Barclays , UBS, RBS and broker ICAP around $2.7 billion over the manipulation of benchmark interest rates such as Libor (London interbank offered rate), which underpins more than $300 trillion of financial products.