Pakistan-Bangladesh relations have been strained since the 1971 independence war in which Bangladeshi nationalists broke away from what was then West Pakistan.

Around 3 million people lost their lives during Bangladesh's fight for independence.

But this month, Pakistanis and Bangladeshis witnessed an unprecedented move between the leadership of the two countries.

Pakistani Prime Minister Imran Khan on Friday congratulated Bangladeshi Prime Minister Sheikh Hasina on her country's 50th Independence anniversary, and invited her for a visit to Pakistan.

"On my own behalf, and behalf of the government and people of Pakistan, I have great pleasure in extending our felicitations on the 50th anniversary of the People's Republic of Bangladesh," Khan wrote in a letter.

The letter has been hailed as an attempt to bring Islamabad and Dhaka closer together.