U.S. Secretary of Commerce Howard Lutnick said trade deals with South Korea and Japan could take significantly more time to complete than the Trump administration's framework agreement this week with the United Kingdom.

Speaking to Bloomberg Television on Thursday, Lutnick said the U.S. will have to spend "an enormous amount of time" with the two countries, adding that agreements with them are not going to be fast deals.

The official, however, did not elaborate on why he expected more time to take place in the negotiations.

Lutnick, meanwhile, said India could be the next country for the U.S. to announce a deal with, but that time will be necessary for bilateral adjustment.

The commerce secretary said the administration's ten-percent baseline tariff remains a "bottom line," warning that the tariffs could further rise unless countries agree to open their markets to American exports.