Pistorius said that he is “consumed with sorrow... pain and sadness” regarding the loss of Steenkamp and explained what it continues to mean to the families.
It was on February 14 last year that Steenkamp, the 29-year-old model and TV star, was found lying on the bathroom floor of the South African Paralympic athlete’s home after she had been shot three times.
On his personal website, Pistorius released the following statement.
"No words can adequately capture my feelings about the devastating accident that has caused such heartache for everyone who truly loved - and continues to love Reeva.
"The pain and sadness, especially for Reeva's parents, family and friends consumes me with sorrow.
"The loss of Reeva and the complete trauma of that day, I will carry with me for the rest of my life - Oscar."
Earlier this week, Steenkamp’s parents, Barry and June, issued a joint statement through their lawyers to add their own remembrance message.
“All we are looking for is closure and to know that our daughter did not suffer on that tragic Valentine's Day," they said.
"As the first anniversary of our beloved daughter's death approaches, we would like to thank all family, friends, the people of South Africa, and the world for their compassion, kind words and comfort shown to us, and for the many letters of condolences we have received."
The 27-year-old Pistorius, nicknamed the Blade Runner, denies murder and claims that he shot Steenkamp accidentally, believing she was an intruder in his home in Pretoria.
Pistorius's trial is due to begin in Pretoria on March 3 and is expected to hear evidence from more than 100 witnesses.
He is charged with premeditated murder, illegal possession of ammunition, as well as two additional gun-related charges.