The Chancellor George Osborne has been in Essex claiming that leaving the EU would be a one way ticket to a poorer Britain.
He spoke alongside political opponents Labour's Ed Balls and Vince Cable from the Liberal Democrats as the Remain campaign staged an event at Stansted Airport.
They warned that Brexit could mean an end to cheap flights and threaten investment such as the new Ryanair training centre which will create 450 jobs.
The Vote Leave campaign pointed out that the Ryanair boss Michael O'Leary said only a few months ago that Brexit would not cause fares to rise.
The Stansted announcement comes after more than 300 business leaders urged Britain to vote to leave the European Union, warning that the country's competitiveness is being undermined by its membership.
In a letter to The Daily Telegraph, they argued that businesses will be "free to grow faster, expand into new markets and create more jobs" if they are unconstrained by EU rules.
Click below to watch a report by ITV News Anglia's Matthew Hudson
Stansted airport has had its busiest ever winter season, with 8.64 million passengers passing through.
Meanwhile, Luton Airport is celebrating two years of continued passenger growth, with 1 million passengers passing through in March.
Sniffer dogs and extra police will be on patrol at at Stansted Airport this weekend as officers attempt to reassure passengers.Read the full story ›
After the Queen declared the Norman Foster terminal building at Stansted open on 15th March 1991 just over a million people a year were using the Essex airport.
In the years which followed a lot has changed. Stansted is now a major hub for low cost airlines and annual passenger numbers have risen to more than 23 million. The terminal has been extended twice.
To mark the 25-year anniversary, ITV News Anglia produced a special programme live from the busy terminal presented by Jonathan Wills and Becky Jago
In 1991 the Queen opened the new terminal building at Stansted. In the 25 years that have followed the airport has undergone rapid growth.Read the full story ›
Stansted airport in Essex has had its busiest February on record with 1.69 million passengers passing through the terminal.
The number of passengers at London's third airport has been growing month on month for nearly two years. The figure for February was up 15% on 2015.
Nearly 23 million passengers used Stansted in the past year, the highest annual total since 2008.
“This strong demand continues to be driven by record numbers of passengers on each flight arriving and departing from Stansted plus airlines increasing capacity on key routes including Berlin, Cologne, Prague and the Scottish cities of Edinburgh and Glasgow.
“Stansted is the UK’s fastest growing major airport at the heart of the UK’s innovation corridor and we remain focused on providing passengers with even more choice of airlines and destinations to better serve our region’s needs.”
Last month British Airways announced it would start flying from the Essex airport to four popular holiday destinations and has just added a weekly flight to Berlin.
A woman has been arrested and fined after staging an impromptu striptease protest about security delays at Stansted airport in Essex.Read the full story ›
A student arrested at Stansted Airport - allegedly on his way to join Islamic State in Syria - will face trial at the Old Bailey.
Cubeyda Jama, 19, from Thornton Heath, was on a flight bound for Bucharest in Romania when he was stopped by police on Friday.
The Middlesex University student, who is originally from Finland and is of Somali descent, is charged with the preparation of terrorist acts.
He appeared at Westminster Magistrates' Court this morning and was remanded in custody. He will appear at the Old Bailey on February 19.
"He was arrested on the 5th February, he was taking a flight to Bucharest which the Crown says was the first step to eventually joining Daesh, formally known as Isis or Isil."
Weeks of roadworks on the M11 begin today - closing the southbound carriageway over night.
The first phase of the £4.7m improvements will be based around junction 8 at Stansted Airport.
The road will be closed from 10pm until 6am for the next two weeks while resurfacing is carried out.
Highways England has warned the work - which will last until the summer - will cause some disruption but insists the improvements will lead to better safety and smoother journeys on the M11.
"We understand this package of schemes will cause some disruption for drivers and we have planned to carry out the work overnight to reduce the impact.
"We have been working with Stansted Airport about these works but I would urge holiday makers and motorists to plan ahead and allow extra time in case of any delays."
At the end of February, work will take place on the M11 at junction 7, with road marking, barrier renewal and resurfacing work being done on the A120 between Trinity and Stansted.
Today is set to be one of the busiest days of the year at Stansted Airport - with more than 40,000 people flying off to 170 destinations ahead of Christmas.
But it will be topped just a few days later - on December 30 - when even more passengers will travel out of the Essex terminal.
In total nearly one million people will use the airport between December 18 and January 2.
Trains and roads are also likely to be very busy.