Pakistan's prime minister assured Kashmiri people living in the Indian-administered part of the divided region that he supports them in their struggle for self-determination.

In his statement Wednesday, Imran Khan condemned New Delhi's decision Aug. 5 to downgrade Kashmir's status, as he began celebrations marking Pakistan's independence day.

"Independence Day is an opportunity for great happiness, but today we are saddened by the plight of our Kashmiri brothers in occupied Jammu and Kashmir who are victims of Indian oppression," Khan said in the statement.

Khan also spent part of the day giving a speech in the Pakistan-administered part of Kashmir. He warned India against any attack on Pakistan-administered Kashmir that diverts attention from human rights violations in the Indian-controlled portion of the Himalayan region.

He said his country has credible intelligence that India could launch an attack and that Pakistan is "fully prepared to respond."

India and Pakistan gained independence in 1947 when British colonialists left the subcontinent. The next year, they fought the first of two wars over control of Kashmir. It ended with the region divided between them though both claim it entirely.

In Islamabad, posters urged residents to express solidarity with Kashmiris while roadside vendors sold Azad Kashmir flags as well as the Pakistan flag commonly displayed on Aug. 14.

Unprecedented security lockdown

India has maintained an unprecedented security lockdown to try to stave off a violent reaction to Kashmir's downgraded status. Protests and clashes have occurred daily, thought the curfew and communications blackout have meant the reaction is largely subdued.

India's Ministry of Home Affairs said there would be heightened security for both Pakistan and India's Independence Day celebrations and for Muslim Friday prayers.

Pakistan has called for an urgent meeting of the United Nations Security Council, saying the move by India's Hindu nationalist-led government threatens international peace and could lead to ethnic cleansing and genocide. Poland holds the council presidency this month and Foreign Minister Jacek Czaputowicz said members would discuss the letter.

Pakistani President Arif Alvi, celebrating Pakistan's independence in Islamabad, condemned India's downgrading of Kashmir's status as a violation of international law and says Pakistan "will not leave Kashmiri people alone."

India celebrates its independence on Thursday and was finalizing preparations for the festivities in New Delhi and in Indian-administered Kashmir on the 10th day of a near-total security lockdown in the Himalayan region. The lockdown is expected to last at least through Thursday.

Pakistan's government has also said India's independence day will be observed as a "Black Day" this year, with flags on government buildings flown at half mast to protest against India's decision.