The UK Serious Fraud Office (SFO), which is prosecuting the case, said on Wednesday that the start of the trial had been postponed from September 4 until January.
No further details were immediately available.
It will be the SFO’s fifth trial of former traders on charges relating to benchmark rate manipulation - and the independent investigator and prosecutor have had a mixed success rate in persuading a jury that bankers dishonestly fixed rates.
Five men have been jailed and eight acquitted in a five-year criminal investigation that underscores the complexity of bringing white collar crime cases.
In its last trial, an expert prosecution witness admitted even he needed help understanding the process and practices he was testifying about.
The latest case is the first to focus on Euribor, the euro interbank offered rate, rather than its London-based equivalent Libor. Five men and one woman have pleaded not guilty to one count of conspiracy to defraud by manipulating Euribor between January 2005 and December 2009.
The former traders include Christian Bittar, who was once one of Deutsche Bank’s most profitable traders, and former senior Barclays trader Philippe Moryoussef. Both are French and now based in Singapore.
Achim Kraemer, a German still employed by Deutsche, and former Barclays traders Colin Bermingham, a Briton, Anglo-Italian Carlo Palombo and Sisse Bohart, a Dane, also face charges.
Authorities have fined 11 financial institutions around $9.0 billion and charged about 30 people in a global inquiry into how banks set rates such as Libor (London interbank offered rate) and Euribor, which determine the rates on trillions of loans and financial contracts globally.
SFO head David Green once hung his reputation on the success of the high-profile rate-rigging investigations - and the agency has succeeded in bringing the cases to trial.
But Prime Minister Theresa May’s Conservative Party has pledged to scrap the SFO and roll it into a broader crime-fighting body if it wins the June 8 national election.
Reporting by Kirstin Ridley; Editing by Ken Ferris