But local competitors are also making a play for what could be one of the most lucrative airline passenger markets in Europe.

Last week, German lowcost carrier Air Berlin may have played down talks of a stock market flotation, but it is clear the airline intends to defend its home turf. The third-biggest European lowfares airline behind Ryanair and Easyjet, Air Berlin was reportedly seeking to raise as much as 700m to buy new aircraft to expand its network.

The airline hired Morgan Stanley and Commerzbank two years ago to seek advice on how to finance any expansion, but a spokeswoman said that, while a flotation isn't imminent, external sources of capital are necessary to increase Air Berlin's footprint.

The following day, Air Berlin appointed its first ever chief financial officer, an executive poached from Commerzbank.

Air Berlin, formerly a charter business, evolved into a discount carrier in 2002. Last year it carried about 14 million passengers and had revenue of 1.23bn That compares to Ryanair's 2005 passenger count of over 33 million, and projected full-year revenue for its 2006 financial year of over 1.7bn, according to NCB.

Whether or not Air Berlin decides on a flotation in the short term, the result looks likely to be the same. Germany's rich pickings are up for grabs.

Ryanair's base at Frankfurt-Hahn has been an epicentre of Germany's low-fares growth. In 1999 just 140,000 passengers transited through Hahn. Ryanair began using the airport in 1999 and last year just over three million people arrived or departed from it.

Ryanair accounts for a phenomenal 95% of all scheduled flights to and from Hahn, making the reliance of the airport's majority owner, Fraport, on Ryanair very conspicuous. Fraport also owns Frankfurt International Airport, which saw almost 51 million passengers pass through its doors in 2004.

The growth of Hahn shows that German travellers can be lured to low-cost travel. German frugality may be a stereotype, but the fact is people are prepared to go to airports that offer cheaper flights. That leaves plenty of scope for the discount airlines.

Consultancy group McKinsey estimated last year that, by 2010, low-fares airlines will carry 24% of European airline passengers, compared to 16% now.

Goodbody Stockbrokers analyst Joe Gill points out that 50% of air passenger traffic between Ireland and Britain is carried by Ryanair, 24% by Aer Lingus (which can now effectively be labelled a low-cost airline) and 4% by EasyJet.

In Germany things are distinctly different. Ryanair accounts for just 13% of air passenger traffic to Britain, and EasyJet 10%. Lufthansa and British Airways each fly 30% of passengers to Britain.

That points to scope for growth for discount airlines.

"The German market is going to recover this year, partly because of the economy showing some signs of life and also because the World Cup effect will be significant, " said Gill. "Over the longer term it's whoever has the lowest costs who will be able to stand longest in whatever market exists.

"Ryanair will be able to withstand any changes and respond in a way that will maintain high margins, " he added.

"EasyJet's experience in Berlin and Dortmund is surprising because its operating costs are significantly above Ryanair and yet it has performed beyond expectations from those two airports. It looks like there is genuine demand in the German economy for low fares and the lowcost carriers are competing against airlines that have traditionally been charging very high fares."

Ryanair has already said it will more than double the number of aircraft based at Hahn by 2010 to 18, and airport management expects that Ryanair will carry 10 million passengers through the airport by 2012.

But real growth has been slow in coming. A stagnant German economy has done little to spur growth in the travel sector and some analysts agree that, while the country has enormous potential, it has been a hard slog for Ryanair.

"It has been tough, but Ryanair is pretty happy with the way Frankfurt-Hahn has performed, " said NCB analyst John Sheehan. "I think there are big opportunities in Germany in coming years.

At the end of day, while there's still the image of the German economy going to the wall, people still take holidays."

The focus on leisure could make the expected low-fares battle in Germany more of a scuffle. Air Berlin has a strong emphasis on flying from Germany to hotspots such as Corfu, Thessalonika, Tenerife and Malta. Although it also serves some Ryanair destinations, the level of crossover is relatively low.

Likewise, Easyjet has always flown from major airports, so is not operating directly on Ryanair's turf.

That leaves some smaller players within the German market, such as Lufthansa's Germanwings, that could find themselves under pressure.

"Air Berlin does continue to grow, and you can see that Lufthansa appears to be ceding some market now on short-haul flights, " said airline consultant Conor McCarthy, a former Ryanair executive who has helped build Malaysian discount carrier AirAsia into an 850m company.

"If you were to take the last two airlines that have yet to admit that low-cost carriers are eating into their shorthaul segment, it has to be Lufthansa and Air France. I think Germany is a big battleground. The fall-out Michael O'Leary has previously predicted hasn't happened, but I suspect that it will. Some of them [other carriers] are out trading on cash reserves. Oil prices haven't eased off and even those that would have hedged their fuel prices, it's caught up on them now."

Over three years ago, the Ryanair chief executive told this newspaper that the company was going to "blow Germany wide open". That may not have happened yet, but it is not likely to be long before Ryanair cements its presence.

At a roadshow presentation last November, Ryanair said that it could double its bases in Europe to 30 by 2012.

It was ready to sign a deal last year to make Lubeck in northern Germany its second German base, but that fell through.

It will only be a matter of time before a new German base is unveiled and Ryanair management will want to expand there sooner rather than later, as the German economy begins to have a pulse again.