Shanghai Electric Power Company withdrew its offer to acquire up to 66.4% of Pakistani power company K-Electric, the manager of the offer said in a notice to the Pakistan Stock Exchange on Monday.

The deadline for making a firm offer for the K-Electric stake expired on April 20 and Shanghai Electric has withdrawn its bid, Arif Habib Limited, the manager said in the notice to the bourse.

K-Electric (KE) is the only electricity generator, transmitter, and distributor for Karachi, Pakistan’s largest city, and its adjoining areas, and the only listed electricity supplier in Pakistan. It was privatised in 2005.

Shanghai Electric has been in talks to acquire a stake in KE for more than half a decade.

The deal has been repeatedly delayed due to regulatory approvals and liquidity constraints as a consequence of mounting circular debt in the country’s power sector. The government of Pakistan owns a 24.4% stake in K-Electric.

In June last year, Shanghai Electric reiterated its commitment to the deal, which was worth approximately $1.77 billion in 2016 but had the likelihood of changing.