Air travel chaos in Britain is purely down to Brexit "shambles" by hobbling recruitment at airports, Ryanair boss Michael O'Leary said on Tuesday.

The CEO of Europe's biggest airline also dismissed threats of summer strike action by what he called "Mickey Mouse" unions in Belgium and Spain covering some Ryanair workers.

And he said his company has dropped a controversial pre-boarding questionnaire for South African passport holders requiring them to answer questions in Afrikaans -- a language commonly used by just 12 percent of South Africans, many of them white.

O'Leary told AFP that "100 percent" of the woes experienced by air passengers in the UK -- including massively long lines and cancelled flights -- was because "Brexit has been a shambles".

"It was delivered by a government led by Boris Johnson that is also a shambles. It was inevitable that Brexit would constrain the labour market, you see," he said.

O'Leary said Britain's decision to pursue a hardline departure from the European Union that put a halt to EU workers filling jobs is largely why it was difficult to quickly ramp up recruitment for ground and security staff at UK passports.

Airports and airlines in several countries, including in the EU and the US, have struggled to cope with surging numbers of travellers, many of them keen to fly after months or years of being grounded because of Covid restrictions.

O'Leary said that unlike European rivals Air France and Lufthansa, low-cost Ryanair had fully bounced back from the pandemic and was flying 115 percent of the passenger loads recorded before the coronavirus hit.

Rising inflation was only pushing more passengers into Ryanair seats, he argued, while acknowledging that the airline was raising ticket prices by around 9 percent.

He said the company's hedging on fuel prices through to March next year was keeping it competitive.

- Strike threats -

But unions in Belgium and Spain are threatening to clip Ryanair's peak summer revenues with strikes later this month to demand better pay and conditions.

O'Leary shrugged off the walk-out warnings.

"We think there will be very few strikes, if any, and those strikes will be meaningless and won't be noticed by anybody," he said.

"We operate two and half thousand flights every day. Most of those flights will continue to operate even if there is a strike in Spain by some Mickey Mouse union or if the Belgian cabin crew unions want to go on strike over here," he added in a media conference.

O'Leary said that, in Belgium, the airline had "reached agreement with the unions representing over 90 percent of our pilots and cabin crew" and was continuing negotiations.

On the controversial Afrikaans test, the Ryanair boss said the company had tried to respond to a rise in detection of false South African passports.

"We suffer a fine of 2,000 euros for every passenger who arrives in Dublin from Bodrum (in Turkey) with a false South African passport," he said.

He added that, while the airline had been asking South African passport holders to answer local general knowledge and geographical questions in Afrikaans, it got rid of the questionnaire.

"We didn't think it was appropriate either. So we have ended the Afrikaans test, because it doesn't make any sense," he said, adding that "South Africa needs to fix its problems".

South Africa's government had called the test "backward profiling".

Afrikaans is just one of 11 official languages in South Africa, and it played a role in the oppression of black citizens during apartheid.