She was supposed to take a special air ambulance of Qatar's royal fleet, but because of a technical glitch, the government of the Middle Eastern country rented an air ambulance from Germany.
Asadur Rahman Asad, a spokesman for the Qatar embassy in Dhaka, said on Friday that the air ambulance was expected to land in Dhaka on Saturday afternoon [this afternoon], reports bdnews24.com.
Earlier on Friday, BNP Secretary General Mirza Fakhrul Islam Alamgir said the air ambulance from Qatar was not coming due to a technical fault.
"If everything goes well, it can arrive on Saturday [today]. If her [Khaleda's] physical condition is fit for the journey and the medical board decides, she will leave for London on Sunday," he said in a statement on BNP's official Facebook page.
Meanwhile, Dr Zubaida Rahman, wife of BNP acting chairman Tarique Rahman, arrived in Dhaka on Friday to accompany Khaleda to London.
After landing, she went directly from the airport to Evercare Hospital Dhaka, where her mother-in-law had been receiving treatment for more than a week.
She stayed in the hospital for around two hours and a half.
Then she left for Dhanmondi to visit her parental home.
Special prayers for Khaleda's recovery were held across the country on Friday.
The BNP organised the prayers in mosques after the Jummah prayers.
Fakhrul and other party leaders attended a prayer at a mosque in Dhaka's Nayapaltan.
The secretary general told reporters after the prayers that Khaleda's illness had started due to the oppression and torture of the previous fascist Sheikh Hasina-led government.
He said Khaleda had dedicated her entire life to establishing democracy in the country.
Due to the injustice done to her by the previous government, she had been in prison for six years, including two years of solitary confinement. Everyone suspected that her illness started from there, Fakhrul also said.
Her condition had been serious, with local and international doctors of very high standards treating her. But it had been decided to take her to a hospital in England as the treatment would have to be done in a more advanced hospital, the BNP leader continued.
Khaleda was taken to Evercare on November 23 after experiencing breathing difficulties.
She was admitted there after tests revealed a lung infection. She was shifted to the Coronary Care Unit (CCU) on Sunday morning when her physical condition deteriorated.
The octogenarian had been suffering from various complications, including heart disease, diabetes, arthritis, liver cirrhosis, and kidney problems, for a long time.
She was sentenced to prison in two cases during the Awami League government, which was toppled in a mass uprising last year, and was imprisoned for more than two years.
The BNP leader was not allowed to go abroad for treatment despite severe health complications and requests from her doctors.
She was released after former prime minister Sheikh Hasina flew to India on August 5 last year in the face of the uprising.
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