London - British racing chief Paul Bittar said that despite two horses being killed in Saturday's Grand National the changes implemented since last year's race needed time to be assessed before any further action was taken.
The Australian - who took over as Chief Executive of the British Horseracing Authority (BHA) in January - added that whilst the deaths of Cheltenham Gold Cup winner Synchronised and the fancied According to Pete were unfortunate there was no need for a knee jerk reaction.
Both fell at Bechers Brook - which had already been modified after fatalities there in the 2011 renewal - Synchronised the first time round and According to Pete being brought down on the second circuit.
It led to calls for there to be further reform of the course but Bittar appeared to suggest in his statement that more time was required before implementing more alterations.
"We extend our deepest sympathies to the connections of Synchronised and According To Pete who we know are devastated at the loss of two home-bred horses which meant so much to them," said Bittar, who held middle to senior posts in British, New Zealand and Australian racing before taking on his present role.
"In November last year, the BHA published the findings from a comprehensive and detailed review of all elements of the Grand National.
"At this stage, we believe it would be premature to suggest that modifications to the course and other changes have not been effective or will not yet prove to be effective.
"Since the Review and the implementation of changes, four races have been held over the course without incident prior to yesterday's running of the Grand National.
"We are reasonably advanced in the process of examining the incidents which led to Synchronised and According To Pete being put down.
"While that process still needs to be completed, it is relevant to point out that although both horses lost their riders jumping Becher's Brook, Synchronised galloped away from the fence seemingly without injury and then subsequently incurred a fracture to a hind leg when jumping riderless, while According To Pete was brought down by another horse on the second circuit.
"Initiatives such as speed sensing on the runners in races over the Grand National course will enable BHA and Aintree to make informed decisions based on factual evidence in our efforts to minimise risk where possible."
Bittar said that the alterations made even before those implemented in the past year had reduced the fatalities markedly.
"The evidence indicates that the changes and improvements in safety made over the years have led to an overall decrease in injury and fatalities, both on the Grand National course and racing in general.
"It is important these matters be judged over a period of time. The decade since 2000 was the safest on record for the Grand National with a fatality rate of 1.5% compared to 3.3% at the start of the 1990's.
"Sadly, there have been two fatalities in each of the last two runnings of the race.
"Naturally our objective is for there to be no fatalities, but we also recognise that we cannot remove risk altogether from such a competitive activity.
"The Grand National is a unique race and it represents a unique challenge for the sport and for its regulation.
"It is a thrilling spectacle, but there is a higher degree of risk involved in the Grand National than other races and for this reason everyone in the sport needs to be conscious of how the race is presented to the public, the general consumer perception and their views of how the race is run."
Winning Grand National trainer Paul Nicholls says the race will never be without risk.
Speaking after Neptune Collonges' victory, he stressed authorities must make the event "as safe as possible".
"There are risks and we all try to minimise them. No stone is left unturned," he told BBC Radio 5 live.
"There is always risk in sport. A lot of people have to grow up, and realise that it is life."
The Australian - who took over as Chief Executive of the British Horseracing Authority (BHA) in January - added that whilst the deaths of Cheltenham Gold Cup winner Synchronised and the fancied According to Pete were unfortunate there was no need for a knee jerk reaction.
Both fell at Bechers Brook - which had already been modified after fatalities there in the 2011 renewal - Synchronised the first time round and According to Pete being brought down on the second circuit.
It led to calls for there to be further reform of the course but Bittar appeared to suggest in his statement that more time was required before implementing more alterations.
"We extend our deepest sympathies to the connections of Synchronised and According To Pete who we know are devastated at the loss of two home-bred horses which meant so much to them," said Bittar, who held middle to senior posts in British, New Zealand and Australian racing before taking on his present role.
"In November last year, the BHA published the findings from a comprehensive and detailed review of all elements of the Grand National.
"At this stage, we believe it would be premature to suggest that modifications to the course and other changes have not been effective or will not yet prove to be effective.
"Since the Review and the implementation of changes, four races have been held over the course without incident prior to yesterday's running of the Grand National.
"We are reasonably advanced in the process of examining the incidents which led to Synchronised and According To Pete being put down.
"While that process still needs to be completed, it is relevant to point out that although both horses lost their riders jumping Becher's Brook, Synchronised galloped away from the fence seemingly without injury and then subsequently incurred a fracture to a hind leg when jumping riderless, while According To Pete was brought down by another horse on the second circuit.
"Initiatives such as speed sensing on the runners in races over the Grand National course will enable BHA and Aintree to make informed decisions based on factual evidence in our efforts to minimise risk where possible."
Bittar said that the alterations made even before those implemented in the past year had reduced the fatalities markedly.
"The evidence indicates that the changes and improvements in safety made over the years have led to an overall decrease in injury and fatalities, both on the Grand National course and racing in general.
"It is important these matters be judged over a period of time. The decade since 2000 was the safest on record for the Grand National with a fatality rate of 1.5% compared to 3.3% at the start of the 1990's.
"Sadly, there have been two fatalities in each of the last two runnings of the race.
"Naturally our objective is for there to be no fatalities, but we also recognise that we cannot remove risk altogether from such a competitive activity.
"The Grand National is a unique race and it represents a unique challenge for the sport and for its regulation.
"It is a thrilling spectacle, but there is a higher degree of risk involved in the Grand National than other races and for this reason everyone in the sport needs to be conscious of how the race is presented to the public, the general consumer perception and their views of how the race is run."
Winning Grand National trainer Paul Nicholls says the race will never be without risk.
Speaking after Neptune Collonges' victory, he stressed authorities must make the event "as safe as possible".
"There are risks and we all try to minimise them. No stone is left unturned," he told BBC Radio 5 live.
"There is always risk in sport. A lot of people have to grow up, and realise that it is life."