WASHINGTON, June 27 (Reuters) - U.S. President Donald Trump and Prime Minister Narendra Modi called North Korea's pursuit of nuclear and ballistic missile programs a "grave threat" to global peace, the White House said in a statement after a meeting of the two leaders on Monday. Trump and Modi pledged to work together to counter North Korea's "weapons of mass destruction" programs and vowed to hold "all parties" that support these programs accountable, the White House statement said.