The deal, which was negotiated between Sugar and O’Leary personally, will begin with ads promoting Ryanair's lowest-price messaging on screens close to the airline's airports in the UK, Germany and Poland.
Ryanair will use Amscreen's Adlive service, which allows a single creative execution to be modified locally using an online portal, to deliver an international campaign with locally controlled content.
The campaign, which will be designed by Ryanair's in-house team, is expected to expand to Switzerland, Austria and other European countries as Amscreen expands.
O’Leary, chief executive of Ryanair, said: "Ryanair has never advertised in this way before, but doing it with Amscreen is a total no-brainer. We can get tailored low-price messages out to millions of potential customers across Europe, at the touch of a button.
"The best thing is if I am sitting at my desk in Dublin and decide that I want to take down the price of flights out of Germany, we can get that ad onto a screen in Berlin within minutes.
"I'm delighted we've come to this arrangement with Lord Sugar and am confident it will deliver immediate real results for Ryanair."Follow @MaisieMcCabe