UPDATE 1-China ambassador says export delays for Brazil vaccine supplies not political

(Recasts with China ambassador comments)

By Eduardo Simões

SAO PAULO, Jan 26 (Reuters) - The issues holding up vaccine supply exports from China to Brazil are due to technical, rather than political obstacles, China's ambassador said on Tuesday, as delays to Brazil's vaccine rollout began to grow.

Some have speculated that China, which for years has been the butt of attacks by Brazil's far-right President Jair Bolsonaro, may have stalled approving the exports as some form of political vengeance. Brazil is waiting for ingredients from China needed to produce two vaccines locally - one from China's Sinovac Biotech Ltd and another from AstraZeneca Plc .

But speaking at a press conference in Sao Paulo, Yang Wanming sought to scotch those rumors.

"Regarding authorization for the export of vaccine supplies, I believe that we all know very well that this is a technical issue and not a political one," Yang Wanming said, without giving more details.

"Vaccines are a weapon to contain the pandemic and guarantee the health of the people and not a political instrument. China attaches great importance to cooperation in the development of the vaccine and we would like to consolidate cooperation."

Yang Wanming said China is committed to helping Brazil after a vaccine developed by Sinovac was late-stage tested in Sao Paulo state. The Sinovac shot is currently Brazil's main hope of slowing the world's second deadliest coronavirus outbreak.

The active ingredient needed to produce 100 million doses of AstraZeneca's vaccine, which will be made at the federally funded Fiocruz Institute, has yet to leave China, adding to delays to Bolsonaro's widely criticized vaccine rollout.

"The company continues to work to release the lots of (active ingredient) for the vaccine as soon as possible," AstraZeneca said in a statement.

Brazilian biomedical center Butantan expects supplies for around 8.5 million doses of the Sinovac vaccine to arrive by Feb. 3, its director said on Tuesday.

Butantan Director Dimas Covas said he hoped the initial shipment, enough to fill and finish some 8.5 million doses, would be followed by a similar load delivered shortly after. He also said Butantan planned to have a factory fully producing the Chinese vaccine by early next year. (Reporting by Jamie McGeever; Editing by Richard Chang)