Samir Ibrahim was among 10 women scheduled to receive the U.S. secretary of state's International Women of Courage Award on International Women's Day Friday, the Middle East News Agency reported.
A statement from the department's spokeswoman, Victoria Nuland, said Ibrahim's award presentation was suspended until alleged remarks she made supporting a bus explosion in Bulgaria that killed five Israeli tourists in July have been investigated.
Ibrahim also allegedly made a remark on Twitter supporting the attack on the U.S. Consulate in Libya in September that killed five people, MENA reported.
Nuland said Ibrahim denied making the Twitter posts in question and said her account was hacked.
Ibrahim was being awarded for taking the Egyptian government to court over virginity tests, which she said she was subjected to after being arrested during a protest in March 2011. She is the coordinator of the Know Your Rights movement, working to raise political awareness and support women's rights.