Spain is set to double its share of production work for the next Airbus passenger jet, the mid-sized A350, while Germany and Britain should see their contributions fall, sources familiar with the matter said.

Spain has been allocated 10 percent of work for the next-generation carbon-fiber A350 designed to compete with Boeing's 787 Dreamliner.

The Spanish share is up from roughly 5 percent for the A380 superjumbo. Industry analysts say this decision stems from a commitment dating back to Spain folding its aerospace assets into Airbus parent EADS in 2000.

Spain's industry ministry declined comment.

The allocations could affect thousands of jobs, with Airbus saying roughly half of its 55,000 workforce will have a role of some kind in the A350 project.

Airbus currently employs some 3,000 people in Spain excluding recently integrated military assets.

Germany is expected to lose 3-4 percent of production work from traditional levels to some 34 percent, the sources said.

This partially reflects another existing deal that would ultimately result in a larger German role for the next generation of Airbus's top-selling model, the single-aisle A320.

The assembly line for the next single-aisle model, code-named A3OX and likely to be developed from late next decade, will be in Hamburg rather than split between Hamburg and Toulouse.

France and Germany have until now been allocated 37.5 percent each of Airbus passenger jet projects in a system once dictated by ownership levels when Airbus started as a consortium four decades ago. It is now owned by EADS.

France would keep its old share and also assemble the A350.

Britain won 18 percent of the A350 in recently concluded talks, down from 20 percent for the A380, the sources said.

Airbus declined to comment but has said in the past that work will be allocated in a way that best promotes efficiency.