Taliban insurgents said on Tuesday that the Pakistani schoolgirl its gunmen shot in the head deserved to die because she had spoken out against the group and praised U.S. President Barack Obama.

Malala Yousufzai, 14, was flown to Britain on Monday, where doctors said she has every chance of making a "good recovery".

The attack on Yousufzai, who had been advocating education for girls, drew widespread condemnation.

Pakistani surgeons removed a bullet from near her spinal cord during a three-hour operation the day after the attack last week, but she now needs intensive specialist follow-up care.

Authorities have said they have made several arrests in connection with the case but have given no details.

Pakistan's Taliban described Yousufzai as a "spy of the West".

"For this espionage, infidels gave her awards and rewards. And Islam orders killing of those who are spying for enemies," the group said in a statement.

"She used to propagate against mujahideen (holy warriors) to defame (the) Taliban. The Quran says that people propagating against Islam and Islamic forces would be killed.

"We targeted her because she would speak against the Taliban while sitting with shameless strangers and idealized the biggest enemy of Islam, Barack Obama."

Yousufzai, a cheerful schoolgirl who had wanted to become a doctor before agreeing to her father's wishes that she strive to be a politician, has become a potent symbol of resistance against the Taliban's efforts to deprive girls of an education.

Pakistanis have held some protests and candlelight vigils but most government officials have refrained from publicly criticising the Taliban by name over the attack, in what critics say is a lack of resolve against extremism.

"We did not attack her for raising voice for education. We targeted her for opposing mujahideen and their war," said the Taliban. "Shariah (Islamic law) says that even a child can be killed if he is propagating against Islam."