Indian foreign secretary Vinay Kwatra has lodged a "strong protest" with the British High Commissioner in New Delhi over the visit to Pakistan-administered Kashmir by Jane Marriott, the United Kingdom's (UK) envoy to Islamabad, a statement from Ministry of External Affairs (MEA) said on Saturday.
"Such infringement of India’s sovereignty and territorial integrity is unacceptable," the MEA said.
The MEA underscored that New Delhi had taken a "serious note of the highly objectionable visit" by Marriott and a UK Foreign Office official to Mirpur in "Pakistan-occupied Kashmir (PoK)" on 10 January.
"The Union Territories of Jammu and Kashmir and Ladakh are, have been and shall always remain an integral part of India," the Indian statement emphasised.
New Delhi has been objecting to visits to Pakistan-administered Kashmir by foreign envoys based in Islamabad.
Last October, India formally lodged a protest with Washington over a similar visit to the region by the American Ambassador in Islamabad.
Pakistan has administered a part of Kashmir it calls as 'Azad Kashmir' since 1948, after Islamabad-backed militants overran large parts of the region in the wake of then ruler Maharaja Hari Singh formally acceding the erstwhile kingdom to India.
The former Indian Prime Minister Jawaharlal Nehru dispatched troops to thwart the advance of the, militants, with the ceasefire line known as Line of Control (LoC).
In 2019, the Indian Parliament formally revoked a Constitutional provision affording special status of Jammu and Kashmir, which previously existed as a state.
The Parliament also voted to bifurcate the former Jammu and Kashmir state to two union territories-Jammu and Kashmir and Ladakh.
Pakistan has objected to the Indian Parliament's decision and since maintained that reinstatement of Kashmir's special status is the pre-condition for resumption of bilateral talks.
Meanwhile, New Delhi rejects Islamabad's "interference" in matters pertaining to Jammu and Kashmir.