Here are the 10 latest developments in this story:
Chaudhry Nisar said "all of Pakistan" wants the teams to travel to India for the tournament, but "the threats are Pakistan specific. It is our responsibility that our players do not face any kind of pressure when they play...Unless we get written assurance from the (Indian) government, we will not allow our team to travel to India."
"How can cricket be played amid threats... Eden Gardens (in Kolkata) has a capacity of one lakh, what if a stone comes from any side. We are just demanding an even playing field," the Pakistan minister added.
On Pakistan's request, a match against India on March 19 has been shifted to Kolkata from Dharamsala in Himachal Pradesh, whose Chief Minister Virbhadra Singh of the Congress said he could not ensure adequate security.
Pakistan Cricket Board or PCB Chairman Shahrayar Khan told NDTV, ""We want to go, we want to play - whenever the permissions come through, we'll go, even if it is on the eve of the match". Both the men's and women's teams have been kitted and waiting from Tuesday to leave for India.
"Matters of security are dealt by ministry of home affairs so you should direct your questions to them," foreign ministry spokesperson Vikas Swarup said in New Delhi when he was asked whether India was sending a written assurance on security to Pakistan.
Mr Swarup also said, "All necessary arrangements including those for security have been made in the past for all international sporting events organised in India...We are confident that the ICC World T20 will also be a resounding success in all aspects."
Sources in Islamabad told NDTV that Pakistan's High Commission in New Delhi had on Sunday contacted the External Affairs Ministry with a request to meet Home Minister Rajnath Singh. "Time for a meeting has not yet been given," the sources said.
"If Pakistan wants an excuse that's a different thing. But India is fully committed to provide adequate security to all teams," said Anurag Thakur, BJP lawmaker and secretary of the Indian cricket board BCCI.
Security concerns arose in Himachal Pradesh after former servicemen protested against the match, alleging that playing Pakistan would hurt the sentiments of the families of soldiers of the state killed in battle against Pakistan or in operations against terrorists from Pakistan-based terror groups.
Pakistan is scheduled to play its first match of the World T20 on March 16 against a qualifier at Kolkata's Eden Gardens. They then play India on March 19, now at the same venue. Pakistan also plays two matches in Mohali in Punjab.