AN ash cloud from the Grimsvotn volcano in Iceland is expected to reach the UK by the early hours of Tuesday morning, the Met Office has said.
It does not necessarily mean there will be airspace closures but makes flight disruption more likely, it said.
The cloud is predicted to affect parts of Scotland, Northern Ireland and the Republic of Ireland.
The event comes a year after ash from the Eyjafjallajokull volcano spread across Europe, causing huge disruption.
The Met Office said there was a possibility of ash moving across the UK towards the end of the week.
But a spokesman said the weather was much more changeable than at the time of last year’s eruption and there was a lot more uncertainty.
The Civil Aviation Authority and the UK’s air traffic control service Nats said they were monitoring the situation closely.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here