The Indian delegation is now self-isolating after two members of the group tested positive for COVID-19.
Dominic Raab said rules had been meticulously applied and had worked effectively and it remained important for the leaders' summit in June to go ahead.
Britain is hosting the three-day foreign ministers' meeting - the first such G7 event in two years - which has been billed as a chance to restart face-to-face diplomacy and a opportunity for the West to show a united front against threats from China and Russia.
India, currently undergoing the world's worst surge in COVID-19 cases, is attending the G7 as a guest and had been due to take part in meetings on Tuesday evening and throughout Wednesday.
Founded in 1975 as a forum for the West's richest nations to discuss crises such as the OPEC oil embargo, the G7 this week addressed what it perceives as the biggest current threats: China, Russia and the coronavirus pandemic.