Trump and Kim are scheduled to meet on June 12 in Singapore.
It also reported that the White House press corps is said to be operating its own media center for journalists who travel with the president. "The advanced team in Singapore is finalizing logistical preparations and will remain in place until the summit begins", Sanders said.
The announcement came a day after the White House revealed that the historic June 12 meeting between the U.S. and North Korean leaders will take place in a luxury hotel on Singapore's resort island of Sentosa. Trump, who had previously canceled the summit, abruptly announced the meeting was back on.
"The discussions have been very positive and significant progress has been made", she said.
The comments risked upsetting the North Koreans days before the meeting with Trump.
"We said, 'Well, we're not going to have a summit under those circumstances, '" he said. "North Korea looks like it's moving along very well".
Trump has been trying to bring together the two countries for some months, in a bid to end North Korea's nuclear weapons programme.
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The oppressive regime is believed to have developed a miniaturized nuclear device that could be placed on a missile that could strike the United States.
The Libya model refers to the denuclearization of Libya, which occurred in the 2000s in exchange for sanctions relief.
The government has said police would make stricter checks of people and personal belongings and items such as public address systems and remotely piloted aircraft system would be prohibited.
He claims to have given the North Korean leader a copy of Trump's ghost-written book "The Art of the Deal" as a birthday gift previous year.
"I am getting a lot of requests from Japan and Korea", said an executive from one of the five-star hotels in Singapore. "So I think you should anticipate that at some point down the road, this will turn into a China-US-South Korea-North Korea talks", Rubio told Fox news.