Pakistan on Monday summoned the British and Indian envoys to the foreign ministry and lodged a formal protest over their ongoing joint military exercises in Jammu and Kashmir.
"Pakistan feels that this is illegitimate activity because Jammu and Kashmir is internationally recognised disputed territory and more than anybody else, Britain should be aware of it," Foreign Ministry spokesperson Tasneem Aslam said at a weekly press briefing.
British and Indian troops last week kicked off a 25-day joint high altitude exercises in Ladakh.
"Pakistan has sent demarches (formal diplomatic protest) to both Britain and India expressing its concern over the exercise plans," Aslam said.
Pakistan had already lodged a protest last week with India over New Delhi's decision to allow trekking in Siachen.
"If India allowed trekking teams in Siachen or if India is doing it now, it does not make it legitimate," the spokesperson said.
"Indian military aggression into Siachen, its presence there and any activities that it sponsors in this area is illegal."
She said Indian presence in the region violates the Simla Agreement of 1972, and Pakistan will raise the issue in the next round of peace talks.
"We have a composite dialogue process with India and Siachen is one of the issue being discussed. Pakistan would certainly raise the issue in the composite dialogue," she said.
Media reports here suggest that Indian and British forces may also conduct joint exercises in Siachen.
To a question, Aslam denied the presence of a nuclear proliferation network operating on Pakistani soil, saying the infamous A Q Khan network was not in operation anymore.
Without elaborating, she claimed more than 300 western companies were involved in nuclear proliferation internationally, adding Pakistan had dismantled all proliferation activities inside its territory.
On questions regarding the arrest of some Pakistani-origin Americans in the US state of Maryland, Aslam said the Pakistan Embassy is looking into it.