Many are thought to have perished in dozens of devastating landslides triggered by the magnitude 7.6 quake on September 30 which buried entire villages.
On Wednesday Holmes visited some of the outlying areas, where he said many communities remained in shock, wondering how and where they can rebuild their lives.
"We've just been looking a horrific landslide, where a village has more or less disappeared, 130-150 people killed, some injured, people in a state of shock," he said.
"So there's a lot of help needed here to rebuild," Holmes added, describing the scene as a "tragic sight".
Hospitals, schools, roads and, according to initial assessments, around 135,000 homes were severely damaged in the quake, primarily in Padang city and the surrounding district.
With so many houses lost, Holmes said the biggest need was for shelter and called on the international community to step up its assistance to recovery efforts.
|Basic essentials like clean water remain in short supply [Reuters]
Last week a joint appeal by relief agencies and the Indonesian government launched a $38m recovery plan indentifying key needs it said needed to be addressed in the next 90 days.
But Holmes added that the scale of destruction and loss wrought by the quake meant that outside assistance would be need well beyond that timeframe.
"People will need relief for months at a time," he said.
"Their livelihoods have often gone, their rice fields have gone, they're going to need food, they need clean water, they're going to need sanitation rebuilding, shelter above all, so this is a question of months and probably a couple of years at least before you can say, even superficially, that life is going to be back to normal."