NEW DELHI, March 25 (Reuters) - India will likely delay deliveries of AstraZeneca COVID-19 vaccine doses to the COVAX facility backed by GAVI and the World Health Organization (WHO) for March and April, the programme's procurement and distributing partner UNICEF told Reuters early on Thursday (Mar 25).

"We understand that deliveries of COVID-19 vaccines to lower-income economies participating in the COVAX facility will likely face delays following a setback in securing export licenses for further doses of COVID-19 vaccines produced by the Serum Institute of India (SII), expected to be shipped in March and April," UNICEF said in an email.

"COVAX is in talks with the government of India with a view to ensuring deliveries as quickly as possible."

Reuters reported on Wednesday that India had put a temporary hold on all major exports of the AstraZeneca shot made by SII, the world’s biggest vaccine maker, to meet domestic demand as infections rise.

UNICEF also said that COVAX participant countries have also been told about lower-than-expected supplies of AstraZeneca doses made in South Korea for March.

"In line with the challenges of the current global supply environment, this is due to challenges the company faces in rapidly scaling up supply and optimising production processes for these early deliveries," UNICEF said.