Liberia's former president, Charles Taylor, is expected to be moved to a British jail after his 50-year sentence for aiding and abetting war crimes in west Africa was upheld by a UN-backed tribunal.

The ruling means the 65-year-old will spend the rest of his life in a high-security prison cell.

A final decision by the special court for Sierra Leone (SCSL) on where he will spend his sentence will be made next week. The UK is the only country that has publicly offered to accommodate him.

There had been speculation that the tribunal might overturn Taylor's convictions, following stricter precedents set in the international criminal tribunal for the former Yugoslavia about what constitutes "aiding and abetting". A series of recent judgments in that court now mean proof is required that senior military commanders have "specifically directed" atrocities.

But the SCSL appeal judges dismissed the Balkans precedents as irrelevant and said Taylor had known at the time that atrocities were going to be committed by rebel forces attacking Sierra Leone's capital, Freetown. They found that the former warlord and political leader had not demonstrated "real and sincere remorse" for his actions.

The judgment was delivered by the appeal chamber of the SCSL in The Hague. Taylor had challenged the 50-year sentence, having been found guilty on 11 counts that included participating in the planning of murder, rape, sexual slavery and enforced amputations. Taylor's lawyers argued that the original trial chamber made systematic errors in the evaluation of evidence and in the application of the law governing what constitutes "aiding and abetting" sufficiently serious to "reverse all findings of guilt entered against him".

The prosecution also appealed against the original decision, saying that Taylor should have been found individually criminally responsible for ordering and instigating crimes committed by rebels in Sierra Leone. It maintained a 50-year sentence was not "reflective of the inherent gravity of the totality of his criminal conduct and overall culpability" and should be increased to 80 years.

Last year the three-judge panel unanimously found that Taylor had been criminally responsible for "aiding and abetting" the Revolutionary United Front (RUF) and other factions carrying out atrocities in Sierra Leone between 1996 and 2002.

The court heard that the Liberian leader knew from August 1997 about the campaign of terror being waged against the civilian population in Sierra Leone and about the sale of "blood diamonds" in return for weapons.

Among the atrocities detailed was the beheading of civilians. Victims' heads were often displayed at checkpoints. On one occasion a man was killed, publicly disembowelled and his intestines stretched across a road to form a checkpoint. "The purpose," Judge Richard Lussick said, "was to instil terror."

Taylor was the first former head of state to face judgment in an international court on war crimes charges since judges in Nuremberg convicted Karl Dönitz, the admiral who led Nazi Germany for a brief period following Adolf Hitler's suicide.

Taylor's conviction was widely welcomed in Sierra Leone but the response in Liberia, where he was once seen as a freedom fighter, was more critical.

Brenda Hollis, the SCSL's prosecutor in the case against Taylor, told the Guardian: "We are happy with the results. My sense was that Taylor felt that nothing he had done was wrong or at least he wasn't admitting to anything.

"Bad things may have happened but he did not know anything about them. He was charismatic, very bright and very manipulative. But sometimes the facts are so overwhelming you can't manipulate them."

Prison authorities in England and Wales have made preparations for Taylor's arrival. The Foreign Office said: "We welcome this landmark verdict for international justice. It demonstrates that the reach of international justice is long and that even heads of state cannot hide behind immunity.

"The verdict cannot erase the suffering of the victims and relatives of those killed, but we hope it helps them to draw a line under that terrible period in Sierra Leone's history.

"We have an agreement with the SCSL to enforce any sentence handed down to Charles Taylor. This is a reflection of our commitment to the SCSL, but it does not guarantee that the UK will enforce Taylor's sentence. The final decision on where Taylor's sentence will be enforced will be taken by the SCSL President."

The average cost of keeping a prisoner in a British jail is around £40,000 a year. Conditions in a British prison are likely to be more restrictive for Taylor than his experiences in Scheveningen jail in the Netherlands, where he has been detained for the past six years: a recent biography, claimed he had fathered a child with his wife during conjugal visits.

The UK's record on holding war crimes inmates is not unblemished. In 2010, the Bosnian Serb general Radislav Krstic, who was serving a 35-year sentence in Wakefield prison, was stabbed in his cell by three Muslim inmates.

Welcoming the tribunal's decision, Elise Keppler of Human Rights Watch said: "Taylor's conviction sends a powerful message that those at the top can be held to account on the gravest crimes.

"With the conclusion of the Taylor case and eight others affiliated with the three main warring factions in Sierra Leone, the special court has been a major force in bringing justice for the horrific abuses committed during that country's brutal armed conflict that ended in 2002.

"The ruling also finds that aiding and abetting can be established where there is a substantial effect – as opposed to a specific direction – on the crimes. A recent controversial ruling at the ICTY required 'specific direction', making it harder to establish liability on aiding and abetting by high-level perpetrators."