A memorial service has been held in south London to mark the second anniversary of the Croydon tram crash.
Seven people died and another 62 were injured, 19 seriously, on 9 November 2016.
Two years on concerns have been raised by Croydon Central MP Sarah Jones that a new a safety body to regulate trams in the UK has still not been created "due to a delay" in government funding.
The government said funding decisions would be made shortly.
A 174-page report into the crash by the Rail Accident Investigation Branch was published last December and made 15 recommendations to improve tram safety.
These included stronger windows and doors on trams, a better understanding of the risk of trams and the creation of a dedicated safety body for UK tramways.
In a letter to the transport secretary, Labour MP Ms Jones said the delays in bringing in a new UK-wide tram regulatory body were "unacceptable".
She said: "This week I learned that almost a year since the RAIB report into the crash, the first and most important recommendation, to create a new tram safety body, has still not been fully implemented due to the Government delaying the funding required to set up the body."
A Department for Transport (DfT) spokesman said "£250,000" had been provided to UK Tram, the umbrella body for the industry, to take forward an action plan.
He added: "While final decisions are being made on funding for the Light Rail Safety Board, we have also set up an industry-wide risk model to improve safety, which the tram operators are taking the lead on."
The tram that crashed was running from New Addington to Wimbledon via Croydon, and was on the approach to Sandilands tram stop shortly after 06:00 GMT when it derailed.
The RAIB report said that all the fatalities and many of the serious injuries were caused by passengers being thrown out of carriage windows.
One survivor, Christine Jess, said she was still "angry" at the operators after learning that not all the recommendations had been carried out.
She said: "From what I know there are things which have been done which should have been done before the tram was up and running.
"It shouldn't have taken lives to be lost, or lives to be changed, in order to start looking at these things.
"Two years on and I'm still suffering, families are suffering. There's still a lot of things that still need to be done, and done quickly."
Eleven of the RAIB's recommendations were aimed at Transport for London (TfL) and Tram Operations Ltd.
TfL's Jonathan Fox said "significant progress" had been made in London and TFL had completed "some of the most vital" recommendations.
A criminal investigation is still being carried out by the British Transport Police (BTP) who arrested the driver on suspicion of manslaughter.
The 44-year-old man, from Beckenham, has been released under investigation, a BTP spokesman said.
At the memorial service
By Tom Edwards, BBC London Transport Correspondent
A grey, cold day, in New Addington and in this tight knit corner of south London at a memorial in front of the parade of shops they came to remember and pay their respects .
Two years ago the crash destroyed families and those who were on-board have endured chronic pain and horrendous life changing injuries.
Some are still panicked by loud noises and the sound of the trams that intersect this part of London.
They struggle to walk far or leave their homes. Some have lost jobs they loved.
But, there is also still anger and frustration by a perceived lack of action.
A watchdog to oversee UK Trams seems years away. Two years on and people here in New Addington feel they do not have the answers they want.