ITAGUAI, Brazil, March 27 (Reuters) - The presidents of

France and Brazil on Wednesday launched a submarine built in the

South American country with French technology in a program that

aims to build Brazil's first nuclear-powered submarine by the

end of the decade.

Presidents Emmanuel Macron and Luiz Inacio Lula da Silva

attended a ceremony in the Itaguai shipyard near Rio de Janeiro,

launching the third diesel-powered submarine built in a $10

billion partnership.

Brazil first lady Janja da Silva smashed a champagne bottle

on the bow of the submarine Tonelero and the two presidents

activated a lever sending the Scorpene-class vessel into the

sea.

The submarine program, begun in 2008 during Lula's previous

presidential term, is a partnership with France's state-run

Naval Group in which defense contractor Thales has a

35% stake.

The Brazilian government said its submarine fleet is needed

to defend the country's nearly 7,500-kilometer (4,700-mile)

coastline and the Atlantic waters, where the country is

developing vast offshore oil fields.

Macron is on a three-day visit to Brazil that aims to

relaunch the bilateral relationship and strategic partnership

that stalled during the previous government of Jair Bolsonaro,

whom the French president criticized for failing to defend the

Amazon rainforest.

Macron landed on Tuesday in the Amazon city of Belem, where

Brazil will host the United Nations COP30 climate negotiations

in 2025. Lula met him there and they pledged to work together to

stop deforestation in the Amazon by 2030.

Macron will meet business executives in Sao Paulo later on

Wednesday and make a state visit to Brasilia on Thursday.