The minister made the remarks in a video statement.
“This efforts will continue until we bring the killers back and execute the verdict," he said.
Killer Noor Chowdhury took shelter in Canada taking chance of Canadian rule that does not permit death sentence. The country does not repatriate convicted offenders of death penalty, the minister said.
“We have appointed our lawyer and trying to bring Noor back," he added.
Another killer Rashed Chowdhury took political asylum in the United Kingdom (UK), Huq said adding that Dhaka is observing the matter and processing discussions.
“Although the whereabouts of the rest three are not clear yet but investigation is underway and hopefully we will succeed one day," he said.
Bangabandhu and almost his entire family were killed on Aug 15, 1975, when a group of assailants went into his residence and assassinated the country's founding father.
Bangabandhu’s murderer Capt (dismissed) Abdul Majed was executed in April this year.
Five other convicts – Syed Farooq Rahman, Sultan Shahriar Rashid Khan, Bazlul Huda, AKM Mohiuddin Ahmed and Mohiuddin Ahmed – were executed in January 2010.
Another killer, Aziz Pasha, met natural death in Zimbabwe in 2001.
Five other convicted killers are -- former Lt Col Khandaker Abdur Rashid, SHBM Noor Chowdhury, Shariful Haque Dalim, Rashed Chowdhury, and Risaldar Moslehuddin.