The National Health Service (NHS) coronavirus app will contain information whether citizens have received their COVID-19 vaccine for international travel.
Transport Secretary Grant Shapps made the announcement on Wednesday.
"It will be the NHS app that is used for people when they book appointments with the NHS ... to be able to show that you've had a vaccine or that you've had testing, and I'm working internationally with partners across the world, to make sure that that system can be internationally recognised," he told reporters.
According to reports, the system will use bluetooth technology to alert those who have the app if they have been in close proximity with someone who has been tested positive for COVID-19.
Britain is likely to allow international travel for non-essential reasons as early as May 17, following a winter lockdown, with a "traffic light system" based on individual countries' COVID risk levels.
Shapps said he would set out into which categories countries would be placed early next month.
"The data does continue to look good from a UK perspective notwithstanding those concerns about where people might be travelling to and making sure that we're protected from the disease being re-imported," he said.