Those attending the gathering on Tuesday in the Afghan capital include Pakistan's army chief General Qamar Javed Bajwa and USA and North Atlantic Treaty Organisation representatives.
Addressing the conference focusing on how to deal with escalating terrorism in the region, Gen Bajwa said the path to regional peace and stability "passes through Afghanistan", the ISPR statement said.
He said a number of Afghans had arrived from other European countries in Brussels to take part in the rally in support of peace and stability in Afghanistan. Army General John Nicholson, the commander of the Resolute Support mission, and the Afghan Army Chief Gen Sher Mohammad Karimi are both in attendance, the handout read. He last visited the war-torn country in October past year and held wide-ranging talks with Afghan President Ashraf Ghani and other leadership.
General Bajwa assured that Pakistani territory is not allowed to be used against any other country and Pakistan expects the same in reciprocity.
The October visit was termed as positive by Afghan leadership as the two sides had agreed to a series of proposals to address the mistrust and security challenges.
And he blamed the recent surge in Taliban attacks on the Islamists' growing desperation.
The participants reminded the world, particularly the European Parliament, that terrorist hideouts in Pakistan not only disrupted security in Afghanistan, but also threatened the entire region, he said.
Last week, the Afghan deputy foreign minister led a delegation of senior civilian and military officials to Islamabad for crucial talks on enhancing cooperation between the two countries.
Afghanistan has been ravaged by a series of deadly terrorist attacks during the last few days, particularly in Kabul, which killed almost 150 people and wounded hundreds more.
Pakistan forces are now involved in fencing its long and mostly porous border with Afghanistan to stop the illegal cross-border movement of the militants.