Pakistan reacted strongly to the seizure by India of a ship carrying equipment used by Pakistan and Bangladesh for UN peacekeeping missions on Sunday.
Foreign Office spokesman Abdul Basit said Pakistan has not been officially informed by India about the detention of the cargo ship.
"The ship coming from Liberia and carrying cargo that was in the use of UN peacekeeping missions has been stopped by India without any justification," he told the media.
The UN cargo on the vessel includes armoured personnel carriers destined for several countries, including Bangladesh and Pakistan.
Basit said, "The ship left Bangladesh after offloading their (cargo) and was also to anchor at Pakistan to offload our consignment."
There was "nothing out of the ordinary" about the ship and "unnecessary hype has been created around perfectly legitimate UN cargo," Basit contended.
The armoured personnel carriers were being used by Pakistani troops who are part of the UN peacekeeping mission in Liberia.
Reports had said that Indian authorities detained the Pakistan-bound ship carrying undeclared military hardware, including rocket launchers and anti-aircraft guns.
The Panama-registered vessel MV Agean Glory sailed from Monrovia in Liberia to Bangladesh via Mauritius.
It then travelled to Kolkata.
Indian authorities detained the ship on Friday after finding out that its clearing agent did not specify that it was carrying weapons.