More than three years on, about 380 bodies of the tsunami's 5395 victims in Thailand are still unidentified.
The US call follows a scandal over funding and alleged fraud within the Thai Tsunami Victim Identification unit that insiders say has damaged morale, possibly slowing or stalling the ID process.
A grant to the Royal Thai Police under which the US gave up to $1.5 million for the purposes of identifying victims of the tsunami concludes on Monday, March 31, 2008.
Officials say only $600,000 from the fund has been used.
Michael R. Turner, press officer at the US Embassy in Bangkok, told Phuketwan: ''The work of the TTVI is not yet completed and it is possible that some of the remaining 380 bodies can be identified.
''The US would like to see a renewed effort on the part of the TTVI to complete their work so that as many families as possible who lost loved ones in the tsunami can finally gain closure.''
A total of 24 Americans died in the tsunami in Thailand, with hundreds more injured and over a dozen requiring extensive hopital treatment.
While many countries as well as Thailand and Burma suffered greater human loss, especially Germany, Sweden, Finland, Switzerland and Britain, in the tsunami's aftermath the US became a key financial contributor.
According to some officials close to the TTVI, accusations of deception and fraud against one officer, Colonel Pornprasert Karnjanarin, Deputy Commander of the Royal Thai Police Foreign Affairs Division, continue to affect morale.
Phuketwan has not been able to establish the precise amount involved in the allegations, but one source said an independent audit found that it was a relatively small sum, covering falsified travel expenses between Bangkok and Phuket.
Whether the amount is large or small, the accusation has caused international embarrassment after a highly successful police operation that at one stage involved officers from up to 40 countries in the world's finest example of forensic detective work.
''When allegations of impropriety were made, the US Embassy raised its concerns to the highest levels of the Royal Thai Police and asked the Thai authorities to investigate the matter,'' Mr Turner said.
''Since then, the Embassy has been in regular contact with the Thai authorities with regard to the grant, and the investigation.
''The investigation is an internal police matter, and as such the Royal Thai Police have control over the length and scope of the investigation.''
Nine officers in Bangkok continue to be attached to the TTVI and go about the work of matching DNA samples and attempting to provide names for victims.
In Ban Maruan, a small village in Phang Nga, to the north of Phuket, the remaining unidentified lie in neat graves in a special cemetery.
To help possible identification at some point in the future, the bodies are encased in metal coffins within concrete tombs.
''The investigation has taken longer than initial expected,'' Mr Turner told Phuketwan.
''But the issues are complicated and cover an extended period of time.
''The fact that the Thai authorities have formally charged a senior official with possible misappropriation of donated funds shows that they appear to be conducting a thorough and serious investigation into the matter.''
Officials at the TTVI deny that the scandal has slowed or stalled the process, or that postings to the TTVI are no longer accepted with the same glee as when the international identification process was at its peak.
Members of the NGOs involved in tracing the relatives of identified victims say their work is continuing with the full cooperation of a small number of TTVI staff based at the cememtery.
It is not clear how many of the remaining bodies of victims are foreign. Most are believed to be poor Thais or Burmese laborers, or their families.
Approximately half of the victims of the tsunami in Thailand were tourists, so about 40 countries undertook to jointly identify and repatriate all bodies.
The TTVI gave the following figures for the number of bodies identified from the time the TTVI took control of the process:
2005, 372 identified; 2006, 489 identified; 2007, 50 identified; to March 26, 2008, nine identified.
The same intense, costly scientific process was not undertaken in Indonesia, Sri Lanka and India, where most of the 220,000 victims perished.
Thousands of victims in those countries were buried in mass graves, without identification.
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