WASHINGTON According to a source familiar with the policy, the Biden administration has plans to require that all foreign tourists to the United States be vaccinated against coronavirus.Reuters reported that the plan will be part the new system after travel restrictions are lifted. Officials have not yet determined when this might happen.President Biden has been under pressure since months to relax restrictions on travel to the United States. This is especially as other countries like Canada and Britain have relaxed their rules.Officials at the White House have stated that they are not planning to lift existing restrictions any time soon due to the rapid spread of the highly contagious Delta variant.