CNN  — 

Thousands of people surrounded the Indian High Commission in central London on Thursday in support of Kashmir, ahead of a planned closed-door consultation by the UN Security Council over New Delhi’s decision to strip autonomy from its part of the disputed Himalayan region.

Waving Pakistani and Kashmiri flags, protestors carrying banners that read “Free Kashmir” squared off with a smaller group of counter-protestors in front of the High Commission.

Both groups were separated by a line of police officers and mounted cavalry unit. Protestors complained about the total communications black out in Indian-controlled Kashmir and said the UN should force India to restore the region’s autonomy.

Sumaiyah Shah said she has not been able to get in touch with her parents in Indian-controlled Kashmir for the past 12 days.

“Because India has put the entire population of Kashmir… under lock-down and curfew,” she told CNN. “I don’t know whether my parents have medicine or food – my mother is a diabetic, she is on insulin,” she added.

The protests comes a week after India’s parliament voted to reclassify the Indian state of Jammu and Kashmir as a union territory, giving New Delhi greater authority over the country’s only Muslim-majority region.

Claimed by both India and Pakistan, the larger Kashmir region has been the epicenter of an often violent territorial struggle between the nuclear-armed neighbors, for more than 70 years.

The state of Jammu and Kashmir is under a tight security lockdown and communications blackout. The repressive measures, in place since August 5, were introduced just days before the Indian government announced that it was withdrawing Article 370 of the country’s constitution.

Thursday’s protest happened on the same day India’s Prime Minister Narendra Modi delivered an Independence Day speech, where he defended his government’s decision, saying he was proud that “‘one nation, one constitution” had become a reality.”

Critics have accused the Modi government of attempting to change the region’s demographics. But Modi has repeatedly insisted that the special status of Jammu and Kashmir had restricted investment and economic growth. Revoking that status was one of the promises he made ahead of recent national elections.

Pakistan has responded to India’s policy change by taking the issue to the United Nations Security Council and has requested member states to intervene.

Pakistan also announced it will downgrade diplomatic relations and suspend bilateral trade with India.

CNN’s Richard Roth, Swati Gupta and Bianca Britton contributed to this report.