Network Rail issued a “full and unreserved apology” on Friday to those families who have lost loved ones in level crossing accidents.
The move from NR chief executive Mark Carne came as a report by MPS severely criticised NR’s treatment of the bereaved families.
The report from the House of Commons Transport Committee found that hundreds of level crossings could be exceeding official death-risk limits and said that on “too many occasions” NR had shown a “callous disregard” for families affected by accidents.
It was particularly critical of NR’s handling of the Elsenham level crossing tragedy in Essex in December 2005, in which Olivia Bazlinton, 14, and Charlotte Thompson, 13, were killed.
Rail regulators should set a target of zero fatalities at level crossings from 2020, the report added.
Mr Carne said: "Today, I wish to extend a full and unreserved apology on behalf of Network Rail to all those whose life has been touched by a failing, however large or small, made by this company in managing public safety at level crossings and in failing to deal sensitively with the families affected.
"Nothing we can say or do will lessen the pain felt by the families of those killed or injured at a level crossing. Today NR is a very different company to the one which existed at the time of these tragic accidents. "
He went on: "As we made clear when we pleaded guilty during the Elsenham court proceedings, it was a watershed in the way we thought about our approach to the risk at level crossings, and how we treat victims and their families. As a result of this transformation, level crossings in Britain are amongst the safest in Europe, but there is still much that we can, and will, do and the committee's recommendations will help us in that endeavour."
Mr Carne said that since 2010 NR had reduced the risk at level crossings by a quarter by investing some £130 million in level crossing safety improvements, including closing almost 800 crossings and appointing over 100 new NR level crossing managers, each with personal responsibility for around 65 crossings.
He said NR had also built 38 footbridges to replace crossings and had mounted a national TV and digital advertising campaign and launched a schools' awareness campaign. It had installed 57 new spoken warnings to announce "another train is coming" and put in new barrier technology at 33 sites which previously had open crossings.
In addition, NR had installed 250 power-operated gate openers to prevent vehicle owners crossing the tracks on foot unnecessarily and fitted 21 crossings with red light safety cameras to dissuade motorists from jumping the lights.
Mr Carne said: "This level of investment and focus continues in the years ahead. Many of the work-streams we have in hand will complement and address many of the committee's recommendations."
He welcomed the progress the company had made, but added: "We will never be complacent when it comes to public safety. As I start my term as chief executive I have made improving public, passenger and work-force safety absolutely integral to everything NR does."
Mr Carne continued: "There is much more we can do....and we have agreed funding of more than £100 million with the regulator to continue this work over the coming five years.
"Restoring public trust relies on openness and with that in mind we have made risk assessment information relating to almost all our 6,300 crossings available on our website. I will continue to explore ways to make our processes even more transparent so we can demonstrate clearly that we treat our responsibility for ensuring public safety with the utmost professionalism."
Speaking on behalf of the Elsenham families on Friday, Mr Bazlinton said: "We are very pleased with the committee's report.
"It totally vindicates our view that NR have not done enough in the past to improve safety on level crossings, and that they treated us very badly - not just us but other families who lost relatives in accidents.
"We are particularly pleased with the emphasis the committee has put on safety, demanding that it becomes the priority: the report says there must be 'an explicit target of zero fatalities at level crossings by 2020'."
He went on: "The committee highlights the lack of transparency around safety concerns at Elsenham. ’Particularly shocking and raises profound questions about NR's internal culture and accountability' is the way they put it - something we, the families, have been arguing in the eight years since the accident which resulted in the deaths of our daughters in 2005.
"Other families shouldn't have to go through what we have experienced, and we welcome the fact that the committee wants to see NR transform the way it which it treats families, the way it handles legal issues and that bereaved families should be entitled to legal support at inquests."
Ian Prosser, the ORR railway safety director, said: "I echo sentiments in the committee's report on safety at level crossings that each and every death at a level crossing is a personal tragedy.
"We are focused on working with NR, local and national governments, industry and the public to close level crossings and minimise the risks."
The report said that all nine deaths at crossings in 2012/13 were "personal tragedies which could have been averted" and NR's chief executive "owes each of the families it let down a full, public apology".
Among the committee's recommendations was a call for NR to improve its communication with the families of people killed or injured at level crossings by appointing a single British Transport Police liaison officer to communicate with affected families until all legal proceedings are concluded.
The MPs also said the Government should extend its legal help scheme to cover representation of bereaved families at inquests.
There were also recommendations concerning driver training, teaching schoolchildren about rail safety, the legal framework for level crossings, road signage and whistleblowing in the rail industry.
Additional reporting by Press Association