A cyberattack on a provider of check-in and boarding systems has disrupted operations at several major European airports including London's Heathrow, the continent's busiest, causing flight delays and cancellations on Saturday.

Collins Aerospace, which provides systems for several airlines at airports globally, is experiencing a technical issue that may cause delays for departing passengers, Heathrow Airport said, having warned of delays.

Brussels Airport and Berlin Airport were also affected by the attack, they said in separate statements.

RTX, Collins Aerospace's parent company, said it had become aware of a "cyber-related disruption" to its software at selected airports, without naming them.

Electronic check-in affected

"The impact is limited to electronic customer check-in and baggage drop and can be mitigated with manual check-in operations," RTX said in an e-mailed statement, adding that it was working to fix the issue as quickly as possible.

The attack has rendered automated systems inoperable, allowing only manual check-in and boarding procedures, Brussels Airport said on its website, adding the incident had occurred on Friday night.

"This has a large impact on the flight schedule and will unfortunately cause delays and cancellations," it said.

The airport said that 10 flights had been cancelled so far, with an average delay of one hour for all departing flights.

Delta expects minimal impact

Passengers with a flight scheduled for Saturday were advised by the affected airports to confirm their travel with airlines before heading to the airport.

Delta Air Lines said it expected minimal impact to flights departing from the three affected airports, adding it had implemented a workaround to minimise disruption.

Berlin Airport said on its website that there were longer waiting times at check-in and it was working on a quick solution. Frankfurt Airport, Germany's largest, was not affected, a spokesperson said.

An official from the operations control centre at Zurich Airport also said it had not been impacted.

EasyJet operating as normal

EasyJet, among Europe's biggest airlines, said it was currently operating as normal and did not expect the issue to impact its flights for the rest of the day.

Ryanair and British Airways owner IAG did not immediately respond to requests for comment.

There were no indications of threats to Polish airports, deputy prime minister and digital affairs minister Krzysztof Gawkowski said.

British transport minister Heidi Alexander said that she was receiving regular updates on the situation.