KUALA LUMPUR, Feb 20 — Troubles are mounting for a Singapore-based Swiss private bank linked to 1Malaysia Development Bhd, with an executive search firm suing it for S$7.1 million in unpaid fees.

According to The Straits Times, BSI Bank Singapore was sued by recruiters Mancano and Associates in August over fees the latter firm claimed it was entitled to for helping the bank employ 23 workers in 2009.

Among the 23 is private banker Yak Yew Chee, who has since been identified as a private banker to Malaysian tycoon Low Taek Jho; Yak also handled the 1Malaysia Development Bhd (1MDB) account at BSI.

According the Mancano’s lawsuit filed in the Singapore High Court, it referred Yak, who had then been attached to RBS Court as its Malaysia head, to BSI that eventually hired him.

The search firm said it was entitled in Yak’s case as well as other successful referrals to a fee of 28 per cent of the hired staff’s first year pay.

In Yak’s case, Mancano said this amounted to S$336,000 as a portion of his S$500,000 base salary, S$350,000 joining fee and US$350,000 bonus.

BSI refused to pay this and other referral fees, arguing that there was no binding agreement between it and Mancano for the executive search services.

BSI in 2013 rejected a S$38 million invoice for Mancano’s services that included the referrals of the 23 staff it was now suing for, again arguing that it was not compelled to pay.

Aside from the legal trouble with Mancano, the Reuters news agency also reported that BSI may be sold as its parent, BTG Pactual Group, was facing financial difficulties and is struggling to continue operations.

In November, BTG Pactual founder and chief executive Andre Esteves was arrested as part of corruption investigations into Brazil energy giant Petrobras, shocking investors and shaking their confidence in the group.

Citing source, Reuters said the Brazilian group is looking to sell BSI to Swiss rival EFG International for an undisclosed sum that could reach US$1.6 billion.

BTG Pactual acquired BSI last year for CHF1.2 billion.

Yak’s role as a key member in Singapore’s’ probe into money laundering linked to 1MDB became public knowledge after he filed a lawsuit to remove a freeze imposed on bank accounts as part of the investigation.

He later withdrew the suit after prosecutors allowed him transfer S$1.2 million into Singapore from abroad in order to pay for expenses and taxes.

Singaporean investigators are scrutinising Yak to determine if his bonuses that skyrocketed from S$649,000 in 2011 to S$10.5 million in 2014 were the product of criminal enterprise.

Yak controls 12 accounts worth S$9.7 million that were frozen by Singaporean authorities for the investigation.

1MDB previously said it was not contacted by authorities in Singapore or elsewhere for their investigations linked to the state-owned firm.