Saudi Arabia is to press Pakistan to boost the number of its troops in the kingdom to help bolster Riyadh’s defences against Islamist militants, including the Islamic State of Iraq and the Levant, also known as Isis.

Nawaz Sharif, Pakistan’s prime minister, landed in Riyadh on Wednesday and met King Salman bin Abdulaziz al-Saud.

While diplomats stress the close ties between the countries, Mr Sharif’s trip — his third this year — comes amid profound challenges facing the bilateral relationship, not least the continued flow of funds from rich patrons in Saudi Arabia to Islamist hardliners within Pakistan. […]