That's according to Emirates CEO Tim Clark.

Andi.

I think probably we're going to see some difficulties.

We're not going to see capacity return to the level that I had hoped in July and August.

I think that maybe in the last quarter.

Clark's comments at Wednesday's virtual summit by aviation consultancy C A P A represent a pessimistic turn.

Last month, he told Reuters he did not believe the recovery would be further impacted by a new wave of infections and restrictions.

Meantime, easyJet CEO Johan Lundgren has called on Britain to set out how it will ease travel restrictions.

On Wednesday, he said there was strong demand for leisure travel, but the success of what could be a make or break summer for European airlines depends on the effectiveness of vaccines.

Britain's already face a holiday ban under current locked down rules.

Earlier on Wednesday, the country's transport minister told people not to book trips abroad or at home for the summer.