UK Prime Minister Boris Johnson has said vaccinations provide a real opportunity to reopen travel, but officials are divided over whether to drop quarantine requirements for visitors inoculated with non-UK-approved vaccines.
Ministers are under pressure to revive the travel industry after months of border restrictions.
Mr Johnson's comments on Thursday are the clearest sign yet the government is planning to scrap mandatory 10-day isolation for fully vaccinated passengers from amber list countries.
"The real opportunity we all have now is to open up travel through the double jab," he said.
"If you look at it ... more than 60 per cent of our population now have two jabs, I think 83 per cent have had one jab, we're really getting through it now. The crucial thing is to come forward and get your second jab."
He reiterated that travel would be difficult this year after indicating this week that "hassle and delays" would be a feature of overseas trips for a long time.
"I’m not going to claim this summer for travel purposes is going to be like any other summer," he said.
"I don’t want to cast a pall over things, but as I said the other day, it will be different."
Officials are still working on whether any new regime would be limited to returning British citizens or apply to all arrivals.
It is understood that non-UK approved vaccines and verification of inoculation status are complicating the issue.
People in Britain can demonstrate their vaccination status via a QR code on the National Health Service app but there is no facility to verify foreign vaccine certificates.
Chancellor Rishi Sunak and Transport Secretary Grant Shapps are pushing for quarantine-free entry for vaccinated travellers from July 19, The Times reported.
However, Mr Hancock and Foreign Secretary Dominic Raab want the plan delayed until August and Mr Johnson is reportedly in agreement.
Plans to drop quarantine requirements for fully vaccinated passengers are expected to be announced as part of the review of the traffic light system.
On Thursday, Environment Secretary George Eustice spoke of the government’s caution regarding foreign travel for vaccinated passengers.
"Nobody likes the draconian restrictions we have had to put in place over this last year as we have wrestled with the pandemic,” he told Sky News.
"We are being cautious because the biggest threat still to our progress against this pandemic and the great progress we have made on vaccination is that there will be another variant somewhere that maybe hadn't been properly detected in another country and that variant is more resistant to vaccination."
Four vaccines are approved for use in the UK – Pfizer-BioNTech, Moderna, AstraZeneca-Oxford and Johnson & Johnson – and the EU uses the same vaccines.
In April, Ireland changed its hotel quarantine rules so travellers vaccinated with EU-approved vaccines could quarantine at home.