Gordon Brown said today he was "angry" and "repulsed" at the reception given to the freed Lockerbie bomber in Libya - but still declined to say if he agreed with the decision to release him.
The Prime Minister insisted the British Government had "no role" in the decision to release Abdelbaset Ali Mohmed Al Megrahi on compassionate grounds, but went on to say that his determination to fight terror remained "absolute".
He also dismissed suggestions that the decision by the Scottish Justice Secretary would undermine Britain's relationship with the US and its other allies against terrorism.
Asked whether he thought it was the right or wrong decision to release Megrahi, Mr Brown said his first thoughts had been with the families of the victims of the Lockerbie bombing.
Speaking in Downing Street, he went on: "I was both angry and I was repulsed by the reception that a convicted bomber guilty of a huge terrorist crime received on his return to Libya.
"When I met (Libyan leader) Colonel Gaddafi over the summer, I made it absolutely clear to him that we had no role in making the decision about Megrahi's future.
"Because it was a quasi-judicial matter, because it was a matter legislated for by the Scottish Parliament and not by us, it was a matter over which we could not interfere and had no control over the final outcome.
"I want to make it absolutely clear, however, that whatever the decision that was made on compassionate grounds by the Scottish Parliament, our resolve to fight terrorism is absolute, our determination to work with other countries to fight and to root out terrorism is total, and we want to work with countries - even countries like Libya, who have renounced nuclear weapons now and want to join the international community - we want to work with them in the fight against terrorism around the world."
Mr Brown's comments, his first in public since last week's release of Megrahi, came as he faced reporters in Number 10 following talks with Israeli prime minister Binyamin Netanyahu.
Speaking alongside Mr Netanyahu, the Prime Minister also rejected suggestions that the row would damage relations with allies against terrorism.
"I don't think what has happened will undermine our relationships with Israel, or the United States, or other countries who engage with us in the fight against terrorism," he said.
"I made it absolutely clear that whatever the decision, that is made on a quasi-judicial basis by the Scottish Parliament, our determination to fight terrorism is clear.
"It is shown in all the action we have taken since September 11, it is shown in the support that we have given in Iraq and Afghanistan to dealing with problems where terrorism rears its ugly head, and it is shown in every action we are taking to protect the British people and protect people beyond Britain against the threat of terrorism."
Mr Brown has been severely criticised by opposition parties for failing to comment on the matter, despite finding time to express his views on the England cricket team's Ashes victory at the weekend.