“We will go back to the ICC with our plan to play in Sri Lanka.
“They did give us a 24-hour ultimatum but a global body can’t really do that. ICC will miss out on 200 million people watching the World Cup. It will be their loss.”
Scotland, as the highest-ranked nation that did not qualify outright for the World Cup, could be handed a late route into the competition if the ICC replaces Bangladesh.
The T20 World Cup, co-hosted by India and Sri Lanka, runs from 7 February to 8 March.
Bangladesh are due to three of their four group games in Kolkata, including against England on 14 February, and the other in Mumbai.
“There is no scope for changing our decision,” said Asif Nazrul, an adviser for youth and sports issues in Bangladesh’s interim government.
“It is crucial to weigh the loss of not playing against the potential catastrophe of pushing players, fans and journalists into a risky regional political situation.
“This is a government decision, as the state is responsible for determining whether its citizens face security risks abroad.”