Pakistan will thwart any attempt to undermine its relations with China, Pakistani President Arif Alvi said here on Saturday, after a terrorist attack killed three Chinese nationals in Karachi earlier this week.

A shuttle passenger van of the Confucius Institute at the University of Karachi was attacked on Tuesday, which has left three Chinese teachers killed.

During his visit to the Chinese Embassy in Islamabad, the president expressed condolences to the Chinese side over the deaths of the teachers, and strongly condemned the attack, saying that Pakistan will spare no effort to fight against terrorism and ensure the safety of Chinese citizens and institutions in the country.

The victims were friendly ambassadors who promoted people-to-people exchanges between Pakistan and China, he said, adding that the terrorists aimed at damaging the Pakistan-China friendship and the construction of the China-Pakistan Economic Corridor.

Pakistan's development and the corridor construction cannot be achieved without the support of China, an "iron brother" of Pakistan, the president stressed.

Pang Chunxue, charge d'affaires of the Chinese Embassy in Pakistan, thanked Alvi for his visit, and said that China strongly condemns the terrorist attack and has asked the Pakistani side to investigate the incident and bring the perpetrators to justice.

China will join hands with Pakistan to ensure the safety of the Chinese citizens, projects and institutions in Pakistan, combat terrorism and promote regional peace and stability, she added.