(Adds reactions from mortgage holder, Polish bank group)
By Alan Charlish and Pawel Florkiewicz
WARSAW, May 11 (Reuters) - Thousands of Polish borrowers were again left in limbo on Tuesday as Poland's Supreme Court delayed a decision on how courts should treat cases involving foreign currency loans.
Many had pursued Polish banks over mortgages they took out in Swiss francs more than a decade ago to take advantage of low Swiss interest rates, only to face far higher costs when the value of the Polish zloty slumped.
"I am mad," 63-year-old retired musician Zbigniew Karpinski, who has a Swiss-franc mortgage on his home in south-western Poland, said of the latest delay in the long-drawn out process.
"It is obviously about dragging it out over time," he added.
Tuesday's hearing, which had already been delayed twice, was expected to lay out how courts should treat key issues in FX loan cases, such as whether banks can charge interest on a loan with a clause deemed to be abusive and when the period during which banks can claim the reimbursement of money begins.
However, at the end of a day which had seen the court and other state institutions evacuated after bomb threats, court spokesman Aleksander Stepkowski said the court had decided to seek opinions from institutions including Poland's central bank, financial regulator KNF and the children's rights ombudsman.
"These institutions have 30 days to take a position," Stepkowski told reporters. However, he said there was no fixed date for the next hearing on the subject.
"It can be said that these relatively non-standard actions are justified, in fact they fit in some way with the rather precedent-setting nature of the legal issue itself," he said.
Tadeusz Bialek, deputy head of the Polish Bank Association said he understood the decision to ask for further opinions.
"If the Supreme Court believes that for a complete picture ... it needs extra expert opinions in this case I think it is hard to judge that negatively," he told Reuters.
Bank Millennium, the Polish unit of Portugal's BCP , said it saw no need to raise capital to cover potential settlements over Swiss franc loans.
Separately, the CEO of state-run lender PKO BP unexpectedly resigned ahead of the hearing.
State-run news channel TVP Info reported that around 40 locations in Warsaw had been evacuated after the bomb threats. (Reporting by Alan Charlish, Pawel Florkiewicz, Justyna Pawlak, Anna Wlodarczak-Semczuk, Alicja Ptak and Anna Koper; Editing by Emelia Sithole-Matarise, Jason Neely and Alexander Smith)