However there is still no guaranteed date for its introduction and Mayor Sadiq Khan has now suggested it may not launch at all.
PM Abbasi welcomed him and said that every Pakistani is proud of his election as Mayor of London and prays for his success.
According to a Dawn news report, this is the first time a mayor of London has visited Lahore.
"To not even be able to guarantee a service will run next year is bitterly disappointing". He arrived in Lahore on Wedesday from Wagah border and met with Punjab Chief Minister Shahbaz Sharif.
"Our reporter asked the Mayor a question in the context of the trip being referred to by senior politicians in the region as a homecoming". Bilateral trade between the United Kingdom and Pakistan is valued at £2.5bn and only two cities in the world provide more investment in Pakistan than London.
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Expressing his thoughts on Twitter, Gandhi said that it is not the Congress party's culture to use such language against political opponents.
The goal of the Mayor's visit is to forge closer ties with the Pakistani business community and focus on meeting the young, up-and-coming generation who will play a key role in the ongoing development of the country.
An Overground train runs from Imperial Wharf to Clapham Junction, on a journey which spans the River Thames.A promised Boxing Day service on the London Overground won't be introduced until at least 2018, if at all, Mayor Sadiq Khan has said in remarks branded "bitterly disappointing" by one London Assembly Member.
Mayor Sadiq Khan informed the prime minister about his successful meetings with officials, media and businessmen after arrival in Pakistan.
He assured the prime minister that he would work towards fostering closer links between London, as its Mayor, and Pakistan.