"You'd need a whole renegotiation", he said. "There is no deadline".
"There's no deadline. We'll pull a team together, but we haven't even done - I mean, it just happened a couple hours ago", Kudlow added.
President Trump had asked two of his economic advisers to explore rejoining the Trans-Pacific Partnership, a trade agreement he withdrew from shortly after taking office a year ago.
"When the USA walked away, they dropped a lot our intellectual property provisions and labor provisions that made the agreement really important", he said.
Rejoining the pact could be a significant change in fortune for many United States industries that stood to benefit from the trade accord and for Republican lawmakers who backed it.
The TPP, a trade deal that was to involve 12 countries including the United States, was conceived under former President Barack Obama as a way to counter China's surging power in the region. AFL-CIO President Richard Trumka, head of the main trade union group, said on Twitter that TPP "was killed because it failed America's workers and it should remain dead".
"The idea was to set a framework that eventually China would have to accommodate", said Massachusetts Institute of Technology economist David Autor.
Mr Trump ordered his staff to evaluate rejoining "on our terms", according to accounts from the meeting. Asian stocks climbed as equities in Japan and Australia advanced. Many current members of the pact feel they already gave considerable ground to the United States to strike the original deal, particularly in sensitive areas like protections for pharmaceutical companies.
But rejoining it could be a complex task. Bauerle-Danzman says the USA would be at a disadvantage if it has to agree to new terms. And any kind of concessions the Trump administration ask for will likely be a tough sell. That could complicate talks as Japan maintains that it has already given all the concessions it could, said trade expert William Reinsch of the Centre for Strategic and International Studies.
Japan's trade minister, Toshimitsu Motegi, warned that it would be hard to renegotiate, saying TPP is a well-balanced agreement based on the varying interests of the signatory nations. Mr Trump's Democratic rival in the 2016 election, Hillary Clinton, also came out against the agreement during the campaign.
China's aggressive response to Trump's tariffs is aimed squarely at goods produced in the USA heartland, a region that helped send him to the White House.
One of the White House officials said that while the president prefers negotiating bilateral trade deals, a multilateral deal with the TPP countries would counter Chinese competition and would be faster than negotiating one-on-one with each of the 11 other nations.