Riyad as-Salihin

'Aishah (May Allah be pleased with her) reported: I heard Messenger of Allah (ﷺ) saying, "The people will be assembled on the Day of Resurrection barefooted, naked and uncircumcised". I said, "O Messenger of Allah! Will the men and the women be together on that Day; looking at one another?" Upon this Messenger of Allah (ﷺ) said, "O Aishah, the matter will be too serious for them to look at one another".

[Al-Bukhari and Muslim].