PARIS, April 3 (Reuters) - France's aerospace industry

has written to the European Commission calling for

"proportionate and assertive" countermeasures if U.S. tariffs

cause significant damage to the key export sector, a person

familiar with the matter said.

The appeal from the country's powerful Gifas aerospace

lobby, whose rotating presidency is held by Airbus,

also calls for any retaliation to be fine-tuned so as to avoid

hurting European companies that rely heavily on U.S. imports.

Gifas did not respond to a request for comment. The European

Commission referred to an earlier statement by its president

Ursula von der Leyen, who said the European Union was prepared

to respond with countermeasures if talks with Washington failed.

President Donald Trump on Wednesday imposed sweeping tariffs

on U.S. imports including 20% on EU goods and 10% on imports

from Britain, home to engine maker Rolls-Royce.

The tone of the letter - juggling retaliation with softening

the impact on French importers - reflects France's position at

the centre of an interlocking supply chain for jets and engines.

France is home to the world's largest planemaker,

Toulouse-based Airbus, which competes with U.S. rival Boeing ( BA )

for sales in the $150 billion global jet market and has

core operations in France, Germany, Spain and non-EU Britain.

It also has a role at the heart of the world's largest

engine maker by the number of units sold, CFM International,

which is co-owned by Safran and GE Aerospace,

supplies both Airbus and Boeing ( BA ), and has mainly stayed below the

trade radar during a 50-year history.

Airbus is also a major customer of Pratt Whitney, the U.S.

engine maker owned by RTX.

Aerospace is France's second-biggest exporter after the

agri-food sector.

Analysts said U.S. airlines would face increased costs as a

result of tariffs on Airbus jets delivered from Europe as well

as a flow of parts feeding the supply chain for maintenance.

With Trump targeting metals and autos in the run-up to

Wednesday's announcement, aerospace and airline executives had

previously played down the prospect of direct tariffs on jets.