Israeli authorities made the wife of the Palestinian ambassador in London interrupt a course of chemotherapy in order to return to Jerusalem or risk losing her residency rights, a trip that hastened her death from cancer, her family claim.

Samira Hassassian was infected by a virus on her plane journey back to London in May and died three months later, aged 57. Her husband, Manuel Hassassian, the Palestinian envoy to the UK since 2005, said the Israeli government had extended her Jerusalem identity papers in 2010 for a year after she was first diagnosed with breast cancer in late 2009, but refused to grant a second extension this year, although the disease had by then metastasised to her bones and she was several weeks into intensive chemotherapy.

"They forced her to go back," Hassassian said. "The doctors had told me she had maybe until the end of the year, so this trip just expedited the process, but it also caused her pain and suffering."

The Israeli embassy in London denied that Hassassian had been refused a second extension. A spokesperson said an extension was granted by the minister of interior, although by then she was already back in Jerusalem.

"If there is a health issue there is no question that she would have had to travel. There is no such policy. It is the strangest allegation I think I've ever heard," the spokesperson said.

Samira Hassassian's London oncologist, Professor Paul Ellis, wrote a medical opinion to support her appeal for an extension on March 29, saying: "She is right in the middle of very intensive treatment and it is definitely not a good time for her to travel. There is the potential for significant infection and she is also extremely disabled by fatigue and nausea."

The embassy spokesman confirmed that a copy of Ellis's letter was in interior ministry files but said it had been unnecessary as an extension was not in doubt. He also suggested that Manuel Hassassian had insisted his wife return unnecessarily to Jerusalem for political motives.

"What kind of husband sends his wife on such a trip when her health and life are at stake? This really is quite low," the spokesman said.

Hassassian said the decision to return was taken by his wife, a US-trained chemist, lecturer in business studies and patron of Palestinian cinema. He says she was determined not to lose what she saw as her rights.

"As far as she was concerned, she was not going to die. She saw herself as battling with cancer. But to force her to go back or lose her rights was inhuman," Hassassian said.

The Israeli embassy claims Samira Hassassian had gone to Jerusalem to seek a second opinion from Hadassah hospital. Her family say she had consulted doctors there so that her condition could be assessed while she was in Jerusalem but that was not the aim of the trip and she would not willingly have broken off a course of chemotherapy to make the journey.

Samira Hassassian's daughter, Nadine, said the ailing woman had tried for several weeks to persuade the Israeli consulate in London to grant a second extension.

"She sent a letter but got no response. They never got in touch with the doctors. On the phone, they told her it wouldn't work. She has to go back to Jerusalem," she said. Manuel Hassassian said that after that, his wife had tried going to the consulate in person, but was not allowed in.

In the face of the Israeli refusal to grant a medical extension, the family said Samira felt she had no choice but return to Jerusalem or lose her East Jerusalem identity papers and the travel documents that those papers entitled her to, and potentially lose the right to return to Jerusalem to live. She flew to Jerusalem in April and returned to London in May, dying on August 19.

Palestinians from East Jerusalem living abroad have to return every two years to renew their residency rights. After seven years overseas those rights are revoked permanently even if the Palestinian involved was born in the city to a family with historical roots there. The rules date back to the 1967 annexation of East Jerusalem, when Palestinian residents were given the status of residents rather than citizenship. They have the option of applying for Israeli citizenship, but many refuse for political reasons, seeing it as recognition of the annexation.

Palestinians and Israeli civil rights groups describe the bureaucracy surrounding residency rights as a weapon in Israel's efforts to reduce the Palestinian population of the fiercely contested city and undermine future challenges to its sovereignty there.

"This has been the consistent policy of Israeli governments, leftist and rightist alike," Sarit Michaeli, of human rights organisation B'Tselem, said. "I lived for 11 years in London and in the US but when I moved back as an Israeli Jew I was able to renew all my residency and citizenship rights. Had I been a Palestinian that would have been impossible."

The Israeli revocation of residency rights has waxed and waned over the years. It reached a peak in 2008 with nearly 4,600 revocations, according to B'Tselem, but last year the number was only 191. It is unclear whether the decline reflects a less rigorous enforcement of the policy or whether fewer Palestinians now meet the criteria.

Civil rights groups say that the physical isolation of East Jerusalem from the rest of the West Bank by a security barrier has also served to reduce its Palestinian population, as have the discriminatory granting of building permits and the demolition of houses without permits.

Hassassian said after his wife's burial he made a point of returning her Jerusalem identity papers and laissez-passer to the Israeli interior ministry.

"They have their papers back now," he said. "They know she does not exist any more."