Qassemi's remarks came on Tuesday after a Danish official accused Iran's intelligence services of trying to kill an Iranian dissident in Denmark.
The Iranian foreign ministry strongly dismissed the claims as a plot against the growing Iran-Europe relations in the current sensitive situation.
"Such allegations are in line with the conspiracies and plots of Iran's enemies who cannot stand the good and growing relations between Tehran and Europe in the current special situation," Qassemi added.
Without providing any evidence, Danish police on Tuesday linked the so-called Iranian intelligence officers of attacking a person in the country. Denmark's foreign ministry then announced in a statement that it had summoned Iran's Ambassador to Copenhagen Morteza Moradian to Denmark's foreign ministry in that connection.
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