The United Kingdom government's likely plan to roll out COVID-19 booster jabs is "needless" and will place undue pressure on the National Health Service, or NHS, the chief executive of vaccine manufacturer AstraZeneca has said.

Pascal Soriot, whose company makes the most widely-used COVID-19 vaccine, said there is currently not enough evidence to justify a booster campaign, which UK Health Secretary Sajid Javid recently said could get the greenlight in the next few days.

"A third dose for all may be needed, but it may not," Soriot wrote in The Daily Telegraph. "Mobilizing the NHS for a boosting program that is not needed would potentially add an unnecessary burden on the NHS over the long winter months. Because NHS staff and resources are scarce, another national mobilization would potentially leave us with fewer resources for cancer screenings and the other care provided by doctors and nurses each day."

Soriot said researchers are still awaiting evidence suggesting that current vaccines lose efficacy to the point where third doses become necessary. Until such evidence emerges, he questioned the logic of pursuing booster campaigns, especially "given how challenging it has been to provide one dose, let alone two" in poor nations.

In late August, the World Health Organization called for a two-month moratorium on booster vaccines in order to reduce global vaccine inequality and to prevent the emergence of new variants of the novel coronavirus.

"The virus will get the chance to circulate in countries with low vaccination coverage, and the Delta variant could evolve to become more virulent, and at the same time more potent variants could also emerge," said WHO Director-General Tedros Adhanom Ghebreyesus.

Tedros said that "vaccine injustice and vaccine nationalism" have led to a "shocking" inequality in the global distribution of jabs. Of the approximately 5 billion doses administered worldwide, 75 percent have gone to just 10 nations. Meanwhile, coverage in Africa remains less than 2 percent.

Despite the WHO's request for a temporary ban on boosters, several rich countries have forged ahead with plans for such campaigns. The UK, United States, France, and Germany are all expected to roll out third shots among certain populations this month. Israel has already begun administering third jabs, and the country's chief COVID-19 officer, Salman Zarka, told The Times of Israel this week that plans for fourth treatments are in the works.

Pharmaceutical company Pfizer, which makes another widely-used COVID-19 vaccine, has garnered criticism for allegedly pushing global governments to adopt booster campaigns.

On Wednesday, Pfizer vice-president, Philip Dormitzer, denied these accusations, telling the Financial Times the company is simply making third shots available, and it is up to policymakers to take "the decision to deploy the solutions".