U.K. Prime Minister Keir Starmer is under fire after he welcomed home an Egyptian prisoner who, in the past, allegedly shared violent and antisemitic content on social media.

British administrations over the years have advocated for the release of Alaa Abd el-Fattah, a dual national of the U.K. and Egypt, who spent much of the last 14 years incarcerated in Egypt.

After receiving a pardon from the Egyptian president, Abd el-Fattah was freed in September. However, he remained in Egypt due to a travel restriction, which was finally lifted, enabling his return to the U.K. this past Friday.

Starmer expressed his joy at Abd el-Fattah’s homecoming, stating he was “delighted” to see the activist reunited with his family in Britain.

Pro-democracy advocate Alaa Abd el-Fattah following his presidential pardon. (AP)

Meanwhile, a senior member of the opposition Conservative Party criticized Starmer for giving a “personal, public endorsement” to Abd el-Fattah.

Robert Jenrick, the Shadow Secretary of State for Justice and Shadow Lord Chancellor, wanted to know whether Starmer was aware of past social media posts in which Abd el-Fattah allegedly endorsed killing Zionists and police. Jenrick also demanded that Starmer condemn Abd el-Fattah’s remarks and withdraw his “unalloyed endorsement” of the activist.

“Nobody should be imprisoned arbitrarily nor for peaceful dissent,” Jenrick wrote. “But neither should the prime minister place the authority of his office behind someone whose own words cross into the language of racism and bloodshed.”

Jenrick, Conservative leader Kemi Badenoch and Reform UK leader Nigel Farage have called for Abd el-Fattah’s British citizenship to be revoked and for him to be deported.

Prime Minister Keir Starmer celebrated Alaa Abd el-Fattah’s return by saying he was “delighted” that the activist had been reunited with his family in Britain. ((Photo by Leon Neal/Getty Images))

The U.K. government later clarified that the prime minister did not know about the “abhorrent” social media posts when he issued the welcoming statement.

The Foreign, Commonwealth and Development Office said in a statement that it had been “a long-standing priority” of governments under both major parties to push for Abd el-Fattah’s release, but it said that does not imply an endorsement of his social media posts.

“The government condemns Mr. El-Fattah’s historic tweets and considers them to be abhorrent,” the statement said.

Abd el-Fattah issued an “unequivocal apology” on Sunday, describing his past comments as the “expressions of a young man’s anger” during regional crises and police brutality in Egypt.

The U.K. government said it considers Alaa Abd el-Fattah’s social media posts to be “abhorrent.” (Andrew Aitchison / In pictures via Getty Images)

Abd el-Fattah’s family in the U.K. had argued that he spent most of the past 14 years behind bars because of his opposition to Egyptian President Abdel-Fattah el-Sissi’s government.

His mother, Laila Soueif, 69, was on a 10-month hunger strike to pressure British authorities to do more to secure her son’s freedom.

Shortly after Abd el-Fattah arrived at London’s Heathrow Airport, critics began circulating his past social media posts. Abd el-Fattah has previously said the comments were taken out of context and were part of a “private conversation” that happened during an Israeli offensive in the Gaza Strip, according to The Times of London.