One of the United Arab Emirates' largest banks has applied to the UK's High Court to appoint administrators for the troubled private hospital operator NMC Health.
The UK-listed firm has been under scrutiny for alleged unauthorised financial activities.
The Abu Dhabi Commercial Bank wants administrators to launch a full investigation into its conduct.
The lender said the move was aimed at safeguarding the future of the company.
The Abu Dhabi Commercial Bank, also known as ADCB, is one of NMC Health's largest lenders with an exposure of $981m (£800m).
NMC Health, which has a debt of $6.6bn, is estimated to have borrowings with more than 80 regional and international creditors.
The country's fourth largest lender, Dubai Islamic Bank, said on Sunday that it had an exposure of $541m to the troubled hospital operator.
Abu Dhabi-based NMC Health is one of the largest healthcare providers in the Middle East with 200 hospitals, clinics and other sites in 19 countries. Most are based in the UAE.
It was founded by Indian billionaire, BR Shetty, in 1974. The company was listed on the London stock exchange in 2012, and in 2017 it was included in the FTSE 100.
The following year the company's market value topped $10bn.
Trouble started for the firm last year after a report by US-based activist investor Muddy Waters alleged that NMC Health had inflated its cash balances, overpaid for assets and understated its debt.
It then made a series of damaging disclosures including alleged theft and excess undisclosed borrowings by former directors. The company lost more than half of its market value within a few weeks and share trading was suspended in February amid several high-profile sackings.
Faisal Belhoul, who was appointed the company's new executive chairman last week, said in a statement that any move to put the group into administration would destabilize its businesses at a time when it was playing an ''important role" in the UAE's response to Covid-19.
After his appointment, Mr.Belhoul had pledged to work with UAE and UK regulators to recover any misused funds.