England manager Gareth Southgate (AFP)
Although no official figures are available, reports suggest only seven of England's 20 top-flight clubs have more than 50 percent of their squad fully vaccinated.
A number of players in Southgate's squad are understood not to have had the jab ahead of Saturday's World Cup qualifier in Andorra.
The government has urged Premier League footballers to take the vaccine, with Sports Minister Nigel Huddleston reiterating the message this week and Southgate would clearly prefer all his players to have the jab.
But he opted not to chastise them in public, instead reiterating that widespread vaccinations were the best way to end the Covid-19 pandemic.
"Everybody knows where I stand on the subject, to move out of the pandemic the only way was a vaccination programme. That was essential," Southgate said.
One report said at least five members of the England squad were refusing to be vaccinated.
Roma striker Tammy Abraham confirmed earlier this week that he had been jabbed after being handed a late call-up for the World Cup qualifiers against Andorra and Hungary.
- 'Personal issue' -
However, Abraham's former Chelsea team-mate Fikayo Tomori, who now plays for AC Milan, chose not to divulge his status, saying it was a "personal issue".
Southgate himself previously received abuse for appearing in a video urging people to have the vaccine.
He said he recognised it was a complicated area but said he had "yet to hear anyone offer an alternative".
"Our doctor has always spoken to the players over the last year-and-a-half about the current situation with infection in the country," he said. "He's always explaining the benefits of the vaccination in that context.
"We can't have much impact over the next two or three days. We can't jab everybody for example."
Southgate's careful handling of the vaccine row epitomises the diplomatic approach that has allowed him to survive five years in the job.
Having led England to the Euro 2020 final, which they lost to Italy on penalties, and the 2018 World Cup semi-finals, Southgate admits only winning a major trophy will satisfy expectations now.
England are on the verge of qualifying for next year's World Cup in Qatar ahead of the away match in Andorra and the game against Hungary at Wembley on October 12.
"Ultimately what I liked last month (in previous qualifiers) was the team, there was no hangover in terms of the disappointment and no complacency in the attitude," Southgate said.
"There is a definite understanding that we are close. We are ranked well in the world and our results have been consistent. Ultimately we want to go one step further."
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