European regulator EASA has become the latest aviation safety agency to order a grounding of Boeing's 787 in the light of problems with its lithium-ion batteries.
EASA adopted the US FAA's emergency airworthiness directive on 17 January.
It affects the two Dreamliners operated by LOT Polish Airlines.
"[EASA] continues to carefully monitor the situation and is prepared to provide any support the FAA may require in their investigation."