Italy's aviation authority ENAC has fined Ryanair $4 million for not looking after stranded passengers during the recent Icelandic volcano crisis.

The news comes as British and Irish authorities are warning again of possible disruptions in the coming week as a new ash cloud forms.

ENA highlighted 178 cases where  Ryanair refused to help stranded passengers between April 17 and 22nd when the ash cloud was most dangerous.

ENAC said Ryanair passengers stranded  in Rome were left abandoned by Ryanair and Italian authorities had to help them instead. Every  other airline helped their passengers ENAC said.

Meanwhile the British government has warned  that  parts of their  airspace may close  from Sunday until Tuesday because of a new eruption.

"Due to continuing volcanic activity in Iceland and prevailing weather conditions, there is -- if the volcano continues to erupt at current levels -- a risk of UK airspace closures," it said in a statement.

The ash cloud is also expected to hover in Irish air space and decisions will be made about flying on Sunday.

The Irish Aviation Authority said Sligo, Donegal, and Knock airports would be open until 0600 GMT while other Irish airports would be open until at least 1200 GMT.

"The IAA is organizing observation flights for tomorrow to check on the level of ash concentrate," it said, stating  it would give  another update on Sunday.