The Malaysian government has come to the frontline of the search for its missing aircraft flight MH370.
Malaysian Minister of Defence Hishammuddin Hussein visited Fremantle on Wednesday to inspect the search vessel GO Phoenix.
"Never in the history of mankind has there been a more complex search than the search for MH370," said Mr Hussein.
The Minister spoke of the close cooperation Malaysia had received from the Australian government.
"The waters may be choppy at times, there will be times when this relationship will be tested, but if we stay true to our cause on MH370, my experience has shown me that nothing is impossible to overcome."
The GO Phoenix is expected to depart on Thursday to return to the search zone in the Indian Ocean. The journey will take almost a week.
Mr Hussein paid tribute to the missing Malaysia Airlines' passengers and their families.
"The fact remains that MH370 has not been found, and all the good that has come from the search pales beside that inescapable fact," he said.
"Words mean little, but the families and friends of those on board MH370 remain in our thoughts and also in our prayers.
"We cannot even begin to understand the pain and anguish they are going through today.
"Let me assure you that MH370 will not be forgotten, that the work thus far will not have been in vain and we, by the grace of Allah, will one day get to the bottom of this tragedy.
"We cannot give up hope. We must continue to hope, for sometimes hope is all we have. We will find MH370."
Another vessel, the Fugro Discovery, departed Fremantle on October 15. Underwater survey operations began on Wednesday.
A third survey ship, the Fugro Equator, used multibeam sonar to map the underwater terrain.
The federal government's coordination centre said poor sea conditions over the weekend had slowed progress.
The Fugro Equator will continue investigations until October 24, when it will depart for Fremantle. It is expected to arrive on October 29.
The mission has already spanned more than 1200 square kilometres of the seafloor.
- with Chenee Marrapodi
