Prime Minister Narendra Modi flagrantly broke with diplomatic protocol to pay a surprise birthday visit to Pakistan leader Nawaz Sharif, betting his personal brand on his ability to revive a troubled relationship, Indian media and analysts said on Saturday. Spurning official talks in the capital Islamabad, India's leader chose to make an intimate trip to Sharif's ancestral residence near Lahore on Friday, where he was celebrating his birthday and the wedding of his granddaughter. A source present in the meeting said the leaders of the nuclear-armed arch-rival nations "chatted like old friends" as they ate vegetarian food, with the Indian premier telling Sharif, "Your sincerity is beyond doubt." Modi's stunning decision to drop in for talks with Pakistan's leader — something former Prime Minister Manmohan Singh failed to achieve in ten years of power — was roundly welcomed in India where it was seen as a highly calculated personal gamble. "Modi has made clear he is willing to risk political capital to make peace," the Indian Express newspaper said in a largely glowing editorial. The visit, announced by Modi on Twitter, gave the appearance of being spontaneous, with Sharif's foreign affairs adviser not able to reach Lahore in time. However, a senior Pakistan official said that security had been planned several days in advance. While Indian media suggested Modi was the driving force behind the visit, a Pakistan official said it was Islamabad's idea to arrange a meeting ahead of formal diplomatic talks set for January. "The goal behind this meeting was to humanise the other side by arranging a visit involving close family members," said the official, adding that some of Sharif's Cabinet members had opposed the visit. Television polls suggested the majority of India's public welcomed the development while newspapers praised the decision to avoid the weight of expectation by staging an informal, unannounced meeting. "Traditional build-up to an Indian PM's visit to Pakistan would have seen different interest groups bringing all kinds of pressure to bear," The Times of India said. Yet members of the opposition Congress party denounced the "unpredictable" act saying it lacked gravitas, with some complaining that such an important meeting should not have been announced on Twitter. In his 18 months in power Modi has shown huge confidence in his personal political skills, announcing economic policies himself and fronting a key state election campaign in Bihar — unsuccessfully — instead of fielding a candidate. "Modi loves to spring surprises — he's disruptive, he's setting aside old taboos," Neelam Deo, a director at Gateway House think tank in Mumbai, said. "He's personalized diplomacy to an extent we haven't seen in India since (India's first prime minister) Jawaharlal Nehru in the 1950s," she said. In Pakistan, opinion polls have shown the population largely backing efforts to bring peace between the neighbours that have fought three wars, along with countless close calls, since gaining independence from Britain in 1947. But there are signs that Pakistan's powerful army, which has ruled the country for around half its existence, was not entirely happy about the visit. A nightly news anchor said he had received messages from intelligence officials expressing pessimism toward Modi's visit while pro-army Twitter accounts that observers believe are run by the military also voiced negative opinions. The last visit to Pakistan by an Indian prime minister was in 2004 by then leader Atal Behari Vajpayee, who is credited with bringing about a thaw in relations with Islamabad. Modi and Sharif have had a stop-start diplomatic relationship since the Indian premier's surprise invitation to Sharif to his inauguration in May 2014. This month, they agreed to resume high-level talks that would cover peace and security as well as territorial disputes, including over Kashmir.