The Punjab chief minister called on Manmohan Singh at his residence in Delhi and asked him to attend the first all-party jatha (a march organised by armed Sikhs) to Kartarpur Sahib next month. File photo of former prime minister Manmohan Singh. (PTI) New Delhi: Former Prime Minister Manmohan Singh will visit the Kartarpur Sahib Gurdwara in Pakistan for the birth anniversary celebrations of Guru Nanak as part of an all-party group next month as he...