National Air Traffic Services (NATS) has closed airspace over west Scotland and Northern Ireland until later today citing a renewed threat from volcanic ash.

Following advice from the Met Office and the Civil Aviation Authority (CAA), NATS placed no fly restrictions over the regions (which include some airports in the Western Isles) until at least 13:00 today.

“Apart from the no-fly zone, normal air traffic control operations are expected within Scottish airspace during this period, including Scottish airports, although some regulation may be required in light of operational experience,” explained NATS in a statement.

NATS is continuing to monitor the latest Met Office information and CAA updates on the density of the ash cloud across the UK, with a further update expected later today.

Ireland

The Irish Aviation Authority (IAA) has, however, confirmed airports in the county will reopen at 13:00.

Dublin, Shannon, Cork, Knock, Donegal, Waterford, Kerry, Galway and Sligo airports are now expected resume normal operations at this time.

“Ireland will not fall within the predicted area of ash concentrations that exceed acceptable engine manufacturer tolerance levels,” explained a statement.

“Our decision to close earlier today was based solely on the safety risks to crews and passengers as a result of the drift south of the volcanic ash cloud caused by the north easterly winds.

“The situation will be reviewed as the week goes on.”

The IAA confirmed international flights travelling though Irish airspace would be unaffected.

Hundreds of flights have once again been disrupted.

All Aer Lingus flights to and from Dublin, Cork, Shannon and Belfast airports to the UK and Europe have been cancelled along with all Ryanair flights into and out of the Irish Republic and Belfast.

However, both airlines expressed “confidence” the situation would return to normal this afternoon.

Eyjafjallajökull

All UK airspace was closed for six days in April, as ash from the Eyjafjallajökull Volcano in Iceland drifted across Europe.

NATS has since been criticised for its slow reaction to the crisis, with airlines calling on the government for financial assistance to help mitigate the economic impact of being grounded.