Most flights in the UK will remain grounded until Monday at the earliest as ash from a volcano in Iceland continues to drift.
Many countries and airlines have grounded fleets amid fears that the ash - a mixture of glass, sand and rock particles - could be catastrophic to aircraft.
BBC News website readers trying to get in and out of the UK have been explaining how the flight ban is affecting them.
CHRISTINE MACANDIE, OSLO, NORWAY
Christine, who's a consultant surgeon, has had to cancel all of her clinics
I am with my husband and two young children stranded in Oslo and tearing my hair out trying to get home.
Despite EU law saying that the airlines have an obligation to provide reasonable meals and accommodation if rerouting takes place several days later, BMI has refused to accept this and we are left paying eye watering prices to stay here - upwards of £400 a day for the four of us.
We had only planned on a two night stay to return Friday lunchtime and looks like our reroute via Copenhagen on Monday is unlikely given the continued closed airspace.
We've looked into so many alternatives which would add up to three days' travel to get home and that's only if trains and ferries are available which they are not. All routes from Scandinavia are booked out for the next week.
There does not seem to be any assistance for UK nationals - the embassy here is closed for the weekend. Surely the governments along with the airlines (who know how many Britons are stranded and where) can co-ordinate alternative chartered ferries etc to get people back to the UK?
Some contingency planning needs to come into force surely this cannot be left to continue indefinitely.
I am a consultant surgeon at the Royal Alexandria Hospital in Paisley so have had to cancel all my clinics until Thursday.
RICHARD GOUGH, VENICE, ITALY
We haven't been told anything by BA apart from faxed messages which have been taped up on the reception in the hotel. We didn't hear anything from BA this morning and assumed that our hotel was going to have to turn people out.
We were under the impression that under the Warsaw Convention that the airline was responsible for a duty of care until the passengers are back in the UK.
We spoke to someone in customer services in BA and they said we've had three nights and we're on our own. Someone else spoke to a person higher up in BA and they said they would fly us back to the UK but we had to sort out our own arrangements before then.
We've looked into it, and it looks like the cheapest option is for my dad to come over in his car, from near Cambridge, and drive all the way down, and drive us back.
The last time BA said anything to us was on Thursday, when we were at the departure gate, and they said: 'We won't be flying.' They haven't even sent a person down to the hotel.
Just to wait until someone calls and saying 'You're on your own' is immoral. It's atrocious.
CHRISTINE BLANCHARD, MADRID, SPAIN
Christine was in Madrid to celebrate her wedding anniversary
I've been stranded in Madrid since Thursday. We were given new flights but these have since been cancelled. Now we've been told that we cannot get a flight until 26 April at the earliest.
We are desperately trying to do something but all trains are fully booked and car hire companies are now charging 1,000 euros (£880) when normally it cost 30 euros (£26). We even tried to group together to hire a coach but there weren't any free.
Although Easyjet has been really good, they're only going to pay for our hotel until Wednesday. Other people in the hotel are not so lucky and are waiting to find out where they stand.
There is a lot of tension at the hotel and although the hoteliers are very sympathetic, the knock-on effect in their own country is causing them a lot of hassle - our hotel manager's eight-year-old son was stranded in Valencia as all the trains back to Madrid had been booked up.
The hotel staff are getting very frustrated - not only dealing with angry customers, but also having to turn away anyone new, genuine guests.
JEROME BERTIN, LONDON
My son is stuck with a school party in Shanghai, China. There are forty 15 to 16 year olds with four teachers there.
They were due to fly back Thursday but have been informed by a business class passenger on the same BA flight they will not be flying before Monday 26 April at the earliest.
We have already looked to see if my son can get back overland and there is a train service from Beijing via Moscow, Copenhagen and Eurostar but it takes 10-12 days....he may have to do this sooner or later.
BA say they will pay for one more night and after that they're on their own. We're not getting a lot of information from the school in Twickenham, but the head teacher is meeting the parents of all the children stuck in China on Monday.
The school opens tomorrow so I guess she's got a bit of a nightmare on her hands. I'm in regular touch with our son - he's run up a £250 mobile phone bill. The LEA has provided additional funding for teachers.
SHIYANA ELIYAS, SRI LANKA
Shiyana has had to cancel all her patients indefinitely
My name is Shiyana Eliyas and I am a Specialist Registrar in Restorative Dentistry. I have lived in the UK for 20 years or so and have been visiting my family in Sri Lanka where I am now stranded.
Under any other circumstance it would be a pleasure to spend a little more time with my family but my work commitments in the UK are hugely disrupted and this worries me.
Sri Lankan airlines have not contacted me with any information and I have had to repeatedly call to find out the little information they are giving. I have received the majority of information from the BBC website.
The airline has made no arrangements for getting the stranded passengers home except for listing them for future scheduled flights. They appear to be reluctant to put additional flights on and the existing scheduled flights are full. I had initially been listed for the 29th April - which is unacceptable.
All my patients are to be cancelled indefinitely from Monday onward and due to booking capacity they are unlikely to be seen for treatment until the end of May or early June. I also have teaching commitments and a conference which I will unlikely be refunded for.
This is the chaos caused to one person. I can only imagine the effects on others and the huge economical cost of this natural disaster.
STEVE BYRNE, COPENHAGEN, DENMARK
I'm part of a five-piece folk band trying get back to Scotland. We were due to fly home on Friday morning, but the flight out of Copenhagen was cancelled. SAS have now cancelled all their flights until Monday and cannot rebook us until Thursday 22nd at the earliest, nearly a week after our original flight.
We've been haemorrhaging money in hotels, so we investigated renting a van to drive back in, but this morning we were quoted £2,000 for a day and a half to drive to Dunkirk.
Thankfully the hotel is still charging us musician-friendly rates, but we don't know how long the generosity will last. Now we're looking into buying a couple of second hand cars to drive home in. We'll be lucky if we break even from the tour in the end.
AL NOONAN, GOA, INDIA
We've had a fantastic holiday for two weeks here in Goa, but now it's time to go home.
What's disturbing us is that we've had no contact from our tour operator since all this began. I rang the resort manager here because we hadn't even seen the rep. Will we have to leave our hotel? Will the operator provide anywhere else for us?
My wife and I are in our 40s so we are prepared for when things go wrong, but there are lots of younger people out here who will have spent all their money and won't know what to do.