Experts have been prevented from reaching the MH17 crash site for a further day, a Dutch official has said.
Virgin Atlantic has joined other airlines in deciding not to fly over Iraq due to safety concerns.
Fears that insurgents could fire rockets at passenger planes have been heightened by the recent downing of flight MH17 in Ukraine.
However some airlines, including British Airways, are continuing to fly over Iraq and have stressed the need for clear guidelines on which routes are safe to fly.
Virgin's decision follows a decisions from aviation chiefs to set up a new task force to ensure information affecting airline safety is effectively collected and distributed.
A "senior level" international task force has been set up by world aviation chiefs to tackle the threat to passenger planes from ground-based weaponry following the downing of Malaysia Airlines flight MH17.
Now a top-level safety conference involving more than 190 nations is to take place under the auspices of the International Civil Aviation Organisation (ICAO). The ICAO's secretary general Raymond Benjamin said that while aviation was still a safe form of travel, Mr Benjamin said that the MH17 disaster had "raised troubling concerns" in respect of civilian aircraft.
He said the task force would be composed of state and aviation industry experts who would see how intelligence regarding the safety of planes could be effectively gathered and passed on to all those affected.
Prime Minister David Cameron was "very humble" when he met the families of victims of the MH17 air disaster, according to one of the parents who attended the meeting.
Barry Sweeney said: "I've got to say Mr Cameron was very humble. He answered every question that was asked of him. He brought a few experts in to talk about crash sites and how the airplane might have come down."
The Newcastle native attended the hour-long meeting with his wife Angela and seven of the 10 families of British victims. His son Liam died alongside his friend John Alder.
The 52-year-old who spoke earlier with ITV News,said: "We basically asked Mr Cameron just to help. The talking I suppose has got to stop and the doing has got to be done."
He added: "I feel very angry and frustrated. It would be nice if they could just stop fighting for a little bit so that we could get all our boys and girls home."
Identifying the victims from the MH17 crash disaster will likely take months, according to one the British investigators working in Holland.
Detective Inspector Howard Way of the Metropolitan Police told ITV News: "There is 80 children amongst the deceased, so yes it's difficult for the people working in the mortuary and also the people working with the families."
Pro-Russian separatists are showing "an appalling disrespect for human decency" in carrying on fighting close to the MH17 crash site, US secretary of state John Kerry has said.
Speaking at a press conference with the Ukrainian foreign minister Pavlo Klimkin, he said: "The fact that not all the remains of the victims of the Malaysian Airlines disaster in Ukraine had yet been recovered had placed "an unsupportable burden on families."
He added that Russian president Vladimir Putin had a choice about whether he choice about whether he could make a difference.
"It's absolutely important that separatists stand back to allow access to the site," he said. "It is 10 days since the crash and investigators have still not received full, unfettered access to the crash site. They have no way of collecting debris."
European governments have reached a preliminary deal to impose economic sanctions on Russia, European Union diplomats have told Reuters.
Among the industries targeted would be the oil sector, defense sensitive technology and dual use goods, one said.
The sanctions will be reviewed after three months, they added.
The families of victims of the MH17 air disaster have arrived at Downing Street to meet with Prime Minister David Cameron.
Among them is Barry Sweeney, father of victim Liam Sweeney, who earlier told ITV News he was hoping today's meeting would lead to some concrete action.
Russia has repeated that Ukrainian forces fired across the border into Russian territory with assault rifles and grenade launchers.
"We officially demand Kiev stop firing at the sovereign territory of the Russian Federation," the foreign ministry said in a statement.
Kiev has denied firing into Russian territory.
Heads of global aviation firms will meet today to discuss potential changes to airspace plans following the downing of Malaysia Airlines flight MH17 over east Ukraine.
The meeting, hosted by the International Civil Aviation Organization (ICAO), is likely to hear calls for wider international powers to intervene when a country fails to monitor threats to its airspace.
The Malaysia Airlines crash occurred after Ukraine left open air corridors that lay within the range of the missile blamed for destroying the jet.
Airlines, represented by International Air Transport Association, will tell the meeting they urgently need improved access to "neutral information" to help them make decisions on where to fly, an industry source said.
"Some countries will never, ever say there is a problem with their airspace even if there really is a problem with their airspace," the source added. "This does not make it easy for airlines."