Railway Minister Nitish Kumar on Tuesday refused to take back his resignation and said he would not attend office in Rail Bhavan.
Prime Minister Atal Bihari Vajpayee had on Saturday rejected the resignation, which Kumar submitted following wrangling in his Samata Party.
"My heart is broken," the railway minister said.
Kumar said there was no question of withdrawing the resignation despite persuasion from his senior party leader and Defence Minister George Fernandes.
Fernandes had spoken to Kumar on Monday night after he had sent in his papers to the prime minister.