Pakistan's leaders Friday assured visiting British Foreign Secretary David Miliband of their commitment to tackle militant groups blamed by India for the Mumbai attacks, officials said. Miliband's visit comes on the heels of a high-profile trip to India, during which he called on Pakistan to show "zero tolerance" toward militants operating on its soil, as the probe into the Mumbai attacks continue. The British foreign secretary, who arrived in Islamabad early Friday, went straight into talks with his counterpart Shah Mehmood Qureshi and Prime Minister Yousuf Raza Gilani, officials from both countries said. He was expected to meet President Asif Ali Zardari and army chief General Ashfaq Kayani before departing Saturday, officials said.