BRUSSELS (Reuters) - AstraZeneca told European Union officials on Friday that it would cut deliveries of its COVID-19 vaccine to the bloc by 60% to 31 million doses in the first quarter of the year due to production problems, a senior official told Reuters. The company was expected to deliver to the 27 EU countries about 80 million doses by the end of March, the official who was involved in the talks said. The company had also agreed to deliver more than 80 million doses in the second quarter, but on Friday was not able to indicate delivery targets for the April-June period due the production issues, the official said. The company said the cut was due to production problems at a vaccine factory in Belgium run by its partner Novasep, the official said.