Politicians tweeted heartfelt condolences as news of Begum Kulsoom Nawaz's death spread on Tuesday.
The official PML-N Twitter account tweeted party president Shahbaz Sharif's confirmation of the news and prayed for her forgiveness.
President Arif Alvi also issued a statement, tweeted by the official account of the President of Pakistan, offering support to her family.
Prime Minister Imran Khan expressed his grief over Begum Kulsoom's death and promised his government's assistance to the Sharif family in this time of grief.
He also directed the Pakistan High Commission in Britain to facilitate Begum Kulsoom's family in London in every way possible.
"Sad to learn of Begum Kulsoom Nawaz's death," his account tweeted on Tuesday evening. "She was a courageous woman of great dignity and confronted her disease with fortitude. My condolences and prayers go to the Sharif family."
The official account of Pakistan Tehreek-i-Insaf (PTI), the ruling party, also paid respect to the former prime minister's wife, saying that the party had "massive respect for her".
Information Minister Fawad Chaudhry, in a video message, said Begum Kulsoom was a "brave woman who stood her ground in difficult times”, as he extended "sincere condolences" to PML-N workers and Sharif family.
PPP Chairman Bilawal Bhutto paid homage to Begum Kulsoom, calling her a "brave woman" who struggled for democracy.
India’s Minister of External affairs Sushma Swaraj also expressed grief over the demise of Begum Kulsoom and extended “heartfelt condolences to the bereaved family”.
PTI Senator Faisal Javed Khan also offered his condolences and prayed that God grants her family "enough strength" to cope with her loss.
Former PML-N minister Khurram Dastagir Khan hailed Begum Kulsoom as a "dissenter against dictatorship" and a "courageous Pakistani".
Bakhtawar Bhutto-Zardari expressed her grief at the news and extended her condolences to the Sharif family, noting that Begum Kulsoom "deserves the nation's respect".
PPP leader Sharmila Faruqi also tweeted prayers that Begum Kulsoom's family finds the strength to cope with the event.
MQM leader Syed Ali Raza Abidi hoped that the government would grant "early bail" to former prime minister Nawaz Sharif, his daughter Maryam Nawaz and son-in-law Captain retired Mohammad Safdar, who are serving sentences in Adiala jail.
Pak Sarzameen Party founder Mustafa Kamal said he was saddened to hear the news and extended support to Begum Kulsoom's family.
National Party leader Hasil Bizenjo prayed that the deceased rests in peace.
Army Chief Gen Qamar Javed Bajwa also extended his condolences "to the bereaved family on [the] sad demise of Begum Kulsoom Nawaz".
Chief Justice of Pakistan also expressed "deep sorrow and grief" on Begum Kulsoom's demise and said that he "prayed to Almighty Allah to shower His blessings upon the departed soul".
Remembering Begum Kulsoom Nawaz
As news of Begum Kulsoom Nawaz's passing spread, friends and acquaintances expressed grief and shared their memories of the three-time first lady and her role in Pakistan's politics.
Journalist Nusrat Javed
"She played an extraordinary role [during Musharraf's martial law era]. In fact, at that time it felt there was a sole face and singular voice of dissent [Begum Kulsoom Nawaz's].
"In a personal capacity, she was a very loving woman. She used to always step forward in times of need, when for example, news of someone surfaced who was in a critical medical condition and did not have the means to seek treatment. She used to help such people quietly.
"She had a very motherly behaviour not only towards the party members but people in general."
PML-N lawmaker Ahsan Iqbal
"She was a very loving lady and my association with her was that of a fellow party member as well as a leader. When martial law was enforced and Nawaz Sharif was jailed, she stood bravely in the face of such dire circumstances and carried forward the party's struggle for democracy. She served as an inspiration for us all."
Former Sindh governor Muhammad Zubair
"She was an outstanding lady and in my opinion, an exemplary one, whatever one's political views are.
"She supported her husband throughout his political career. And when Nawaz Sharif went to jail, she came out and engaged in a political struggle, even though it was unheard of for a woman in Pakistan to do so at the time.
The few times that I met her, she came across as a good Pakistani housewife; she was educated, articulate and intelligent."
Journalist Meher Bokhari
"It's very unfortunate for the children and Mian [Nawaz Sharif] Sahab. Maryam Nawaz would credit [her political standing to] her mother ─ her father was not in favour of her entering politics. Her mother said that she [Maryam] was ready.
"She played a crucial role in convincing her husband given how well she [Maryam] had campaigned for the 2013 elections ... It was Begum Kulsoom who broke the family's long-held tradition of not allowing women to foray into politics."
ANP leader Zahid Khan
"Whenever I met her during talks between leaders, I found her to be a very wise and prudent woman. I never once saw bitterness in her temperament. She was the sole lady to stand up in the face of Pervez Musharraf's dictatorship. Even the male members of the party were not as bold as she. It is not just a loss for the party but for the whole nation."
Journalist Mujahid Barelvi
"I was recalling the time when I was on the flight during the [Sharifs'] visit to Azerbaijan and Madina. I had the opportunity to join them for breakfast.
With other leaders and their families, I had never known spouses to have that sort of presence. In her case though, I observed her to be a very impressive personality. She used to join in during conversations and even quipped when Nawaz asked 'Is there no Nihari or paaye for breakfast?' to say 'No we have put a stop to all these things'.
It is very unfortunate the way she was consumed all of a sudden by such an illness for a whole year and which caused so much suffering for the family."
Journalist Iftikhar Shirazi
"There is no doubt that in 1999, when the military coup took place and Nawaz Sharif's government was dissolved, all the bigwigs of the N-League were not fighting his case (like they should have). In such dire times, Kulsoom Nawaz took matters into her own hands. She took to the streets and held protests the result of which was a secret agreement which then led to Nawaz Sharif and his family living in exile in Europe for 10 years.
"In such stressful times, no other member of the party played such a crucial role, as she did. They all either parted ways or stepped back or changed loyalties, but either way they did not stand with Nawaz Sharif.
"Even now, when he was disqualified and his NA-120 Lahore seat was left vacant and she stood for elections, it was unfortunate that she was unable to appear in the assembly and take oath as a parliamentarian; yet it can be said that she was a member of parliament for more than a year.
"She may not have forayed into politics the way her husband or the Sharifs in general had, but whenever dire circumstances arose, she was with Nawaz Sharif. She served as his advisor as well; whenever she was needed, she never refused to serve the party in any way she could and to bring the family out from all the tough times it went through."