British Prime Minister Gordon Brown has asked President Asif Ali Zardari to do more to root out terrorism emanating from Pakistan's territory after police in the UK arrested a dozen Al-Qaeda suspects, including 11 Pakistanis, over a 'very big terrorist plot'.

"Prime Minister Brown telephoned President Zardari and the two leaders discussed matters relating to bilateral relations as well as the fight against terrorism," Presidential spokesman Farhatullah Babar said in Islamabad, without giving details.