Former prime minister Nawaz Sharif's wife, Kulsoom Nawaz, is "being prepared" to undergo her first chemotherapy session in the United Kingdom, her daughter announced on Twitter on Tuesday.

Maryam Nawaz tweeted a picture of Kulsoom in the hospital, with Nawaz by her side, and thanked her followers for their "valuable prayers".

She posted another picture of her parents with the caption "in sickness & in health... A solemn vow".

Kulsoom was diagnosed with early-stage lymphoma in August when she suddenly left for London for a checkup. She has since undergone three surgeries and remains in London.

In September, Kusloom won the NA-120 by-election. The seat had fallen vacant after her husband was disqualified by the Supreme Court in the Panama Papers case.

The election campaign leading up to September's by-polls was run by Maryam Nawaz.