PARIS (Reuters) - Airbus (>> Airbus SE) said on Tuesday it had uncovered inaccuracies in its filings to U.S. regulators over arms technology sales, drawing the United States for the first time into a scandal over alleged misconduct at Europe's largest aerospace firm.

Airbus also warned about potentially significant fines resulting from existing bribery investigations in Britain and France over the use of middlemen in jetliner sales, which have triggered a sweeping internal investigation.

But it said it was too early to guess the size or timing of any European penalties, or the outcome of the new U.S. findings.

Airbus shares rose 3.6 percent after a smaller than expected drop in third-quarter profits despite delays in some aircraft deliveries.

However, the gains were overshadowed by news that Airbus had itself unearthed inaccuracies in past filings to the State Department on defence technology exports.

These involved inaccurate statements under a section of the U.S. International Traffic in Arms Regulations (ITAR) that governs the use of commissions and agents.

Airbus said the flaws were first discovered in November 2016 and confirmed in an internal review completed in late July.

Finance Director Harald Wilhelm said the European company had not disclosed any secrets about U.S. technology and that the issue was restricted to the use of sales agents and commissions, governed under part of the ITAR rules.

It is separate from investigations into the use of agents in commercial airplane sales, which are not subject to the same U.S. controls as weapons exports, but do have some U.S. restrictions over the use of advanced navigation technology.

"This is about defence equipment and services related to it," Wilhelm told reporters.

CO-OPERATION

Airbus has been badly shaken by the existing corruption probes, which have already clipped aircraft sales.

Chief Executive Tom Enders is under increasing pressure over the conduct of the internal investigation, which sources familiar with the matter say has angered staff and alarmed French networks of influence abroad.

Le Canard Enchaine said in an advance copy of its Wednesday edition that French President Emmanuel Macron hoped to find a French replacement for Enders with German Chancellor Angela Merkel's support. France and Germany each hold 11 percent of Airbus.

However supporters of German-born Enders say such a move may set up a struggle with the Airbus board, which won independence from state interference in a 2013 governance shake-up backed by Macron, as adviser to former president Francois Hollande.

"We don't comment on speculation," an Airbus spokesman said.

Wilhelm declined to say whether the latest disclosure could lead to an investigation by the U.S. Department of Justice, which has so far stayed out of the European bribery probes.

The DOJ shares jurisdiction for ITAR rules with the State Department where criminal activity is suspected. The DOJ and the State Department declined comment.

A person familiar with the latest case said it involved inaccuracies over both names of agents and amounts paid.

That echoes inaccuracies in applications for UK export aid which triggered the separate UK and French probes, but the now-disbanded headquarters team at the centre of those accusations was not involved in the U.S. ITAR process, sources familiar with the matter said.

Airbus hopes that by self-reporting and co-operating fully with the European probes it can qualify for a deal similar to a $680 million settlement granted to Rolls-Royce (>> Rolls-Royce) this year.

Legal experts estimate Airbus faces fines in the billions because of the scale of suspect paperwork dating back years.

The cost of legal advice and running its own investigations pushed up headquarters cost sharply in the third quarter.

The world's second largest planemaker after Boeing (>> Boeing Company (The)), posted third-quarter core operating earnings of 697 million euros ($811 million), down 4 percent on lower deliveries.

It took a further small charge for the troubled A400M military project and warned of further costs later this year.

It reaffirmed its 2017 guidance but abandoned an informal goal of 720 jet deliveries that was higher than the official target of 700. Airbus has unusually given different written and verbal delivery targets for several quarters in a row.

The shortfall is chiefly the result of delays in the supply of engines for the A320neo. Airbus now expects to deliver fewer than 200 of the aircraft this year, compared with a target of "around 200". But analysts say an end to delays is in sight, driving up the share price.

($1 = 0.8595 euros)

(Reporting by Tim Hepher and Cyril Altmeyer, Additional reporting by Jean-Baptiste Vey and Mike Stone, Editing by Mark Potter and Greg Mahlich)

By Tim Hepher and Cyril Altmeyer

Stocks treated in this article : Airbus SE, Boeing Company (The), Rolls-Royce