WRAPUP 7-French march in record numbers against pension plan

* Strikes disrupt public transport, flights, ports

* Unions say 3.5 mln strikers, government says 1.2 mln

* Prime minister says no more room for concessions

(adds union leader, prime minister's quotes)

By Nick Vinocur and John Irish

PARIS, Oct 12 (Reuters) - French demonstrators hit the streets in record numbers on Tuesday in their latest protest against President Nicolas Sarkozy's plan to shake up the pension system, and striking transport workers badly disrupted trains.

Marches across France drew a higher turnout, police and unions said, than four earlier protests against reforms that would make people work longer for their pensions in order to curb a ballooning deficit in retirement coffers.

Yet Sarkozy, a dogged conservative who is aiming to get his flagship reform passed before he takes on the rotating presidency of the G20 group of rich and developing nations in mid-November, looks unlikely to back down.

French media dubbed Tuesday the start of the "final battle" against the pension reform, which is on track to become law by the end of October. The reform will raise the minimum retirement age to 62 from 60, and the age at which workers receive a full pension to 67 from 65.

The reform, which could help safeguard France's cherished AAA credit rating as pension costs soar in the years ahead, has become one of the biggest battles of Sarkozy's presidency.

Powerful unions, which crushed a 1995 attempt to reform the system in a country that is fiercely attached to its generous social benefits system, said the high turnout was a wake-up call to Sarkozy's government to return to the negotiating table.

"Your position is untenable. You cannot witness more and more people in the streets each week, more and more people joining the strikes, and stick to your intransigent position," Bernard Thibault, head of the CGT union, told France 2 television.

Unions said 3.5 million people had joined in the street marches, up from their estimate of 2.9 million in the Oct. 2 demonstration. The interior ministry put the number at 1.23 million, a rise of nearly a third.

The latest round of strikes disrupted air and train travel and shut the Eiffel Tower during the afternoon for lack of staff. Unions are threatening more open-ended walkouts, but Sarkozy's government has vowed not to cave in.

"We are determioned to see this reform through to its end," Prime Minister Francois Fillon told parliament. "We have reached the limit of the (concessions) that are possible."

Last week Sarkozy offered concessions to mothers close to retirement age who give up work to raise several children, and analysts do not expect him to give up much more ground.

"It's part of the ritual but nonetheless impressive," Gilles Moec, an economist at Deutsche Bank in London, said of the protests. "Probably not enough to block the pensions bill, but enough to block any further structural reform." <^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Graphic on austerity protests: r.reuters.com/war95p For more stories on pension protests, click on [ID:nLDE68911U] For a Q&A on pension protests, click on [ID:nLDE69B0HA] For stories on austerity protests in Europe [ID:nLDE6961RO] ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^>

EIFFEL TOWER SHUTS

Walkouts reduced flights from Paris's main airports by as much as 50 percent. One in three high-speed TGV trains were running, though international trains operated more frequently.

The Paris metro ran limited services, sea ports were disrupted and oil refinery closures due to related dock worker strikes raised the spectre of fuel shortages. [ID:nWEA1848]

Students, concerned that making older people work longer would shut off job opportunities for them, chanted slogans, waved banners and climbed onto the roofs of bus shelters with loudspeakers. There were protests at about 300 schools.

"This law ignores the reality for young people," said Eloi Simon, 21, a student near Paris. "It's hard enough to find a stable job and if this goes through it will be even harder."

Spending cuts across deficit-plagued Europe have sparked angry protests, most notably in Greece and Spain.

France's parliament has now passed the core clauses of the pension bill and Sarkozy is betting on protest action waning in the coming days, especially among those who lose pay when they walk out.

Unions are planning more action for Saturday and some have threatened open-ended strikes in the days ahead.

Budget airline Ryanair (RYA.I) urged the European Commission to ban strikes by what it called "overpaid, underworked" air traffic controllers after it was forced to cancel 250 flights.

"Striking French ATC staff are the modern equivalent of highwaymen," outspoken chief executive Michael O'Leary said.

(Additional reporting by Gerard Bon, Emile Picy, Elisabeth Pineau, Tim Hepher, Helen Massy-Beresford and Daniel Flynn; Editing by Catherine Bremer and Noah Barkin)