GENEVA (REUTERS) - The World Health Organisation's Europe director Hans Kluge said on Thursday (Jan 28) that vaccine manufacturers were working non-stop to plug shortfalls in supplies to countries struggling to curb the Covid-19 pandemic and urged them not to jostle for deliveries.

"Solidarity does not necessarily mean that each country in the world starts (vaccinating) at exactly the same moment... The good understanding is that no one is safe before everyone is safe," Mr Kluge told an online news briefing.

Asked about delays in expediting Pfizer and AstraZeneca vaccines to patients across the 27-nation European Union, Mr Kluge said governments and manufacturers should work together to address "teething problems" in the roll-out.

"The reality is there is a shortage of vaccines... (But) we don't doubt that manufacturers and producers are working 24/7 to bridge the gaps and we're confident the delays we are seeing now are going to be made up by extra production in the future."

As he spoke, Europe's fight to secure Covid-19 vaccine supplies sharpened when Britain demanded that it receive all the shots it paid for after the EU asked AstraZeneca to divert supplies from Britain.

The EU, whose members are far behind Israel, Britain and the United States in dispensing vaccines, is scrambling to get supplies just as the West's biggest drugmakers slow deliveries to the bloc due to production problems.

"We need to be patient, it will take time to vaccinate," Mr Kluge said, adding that a total of 35 countries in Europe had launched vaccinations with 25 million doses administered so far.

"These vaccines have shown the efficacy and safety we all hoped they would... This monumental undertaking will release pressure on our health systems and undoubtedly save lives."

He said continued high rates of transmission and emerging variants of the virus made it urgent to vaccinate priority groups, but said the rate of vaccine production and distribution was not yet meeting expectations.

"This paradox, where communities sense an end is in sight with the vaccine but, at the same time, are called to adhere to restrictive measures in the face of a new threat, is causing tension, angst, fatigue, and confusion. This is completely understandable in these circumstances."