U.S. President Donald Trump said Friday he expects to receive a "positive letter" from North Korean leader Kim Jong-un.

Speaking to reporters aboard Air Force One, Trump said that he knows a personal letter from Kim is going to be delivered to him, adding that it was handed over at the border the day before.

This border Trump refers to is suspected to be the inter-Korean border, but a detailed route of the letter's delivery was not provided.

Trump said the letter will likely be delivered to him by Secretary of State Mike Pompeo and added that "It's an elegant way, the way it used to be many years ago before we had all of the new contraptions that we all use." 

Trump also said he thinks it's going to be a positive letter. 

The letter could have been delivered during Friday's general-level military talks between the U.S. and North Korea held at the Panmunjeom border village to discuss the excavation of the remains of American soldiers killed in the Korean War.

The latest correspondence is the North Korean leader's fourth letter to Trump.