LONDON (AP) — U.S. President Donald Trump’s national security adviser says the United States is ready to negotiate a post-Brexit trade deal with the U.K. “in pieces” to help speed the process.

John Bolton met with British Prime Minister Boris Johnson on Monday. Johnson’s Downing Street office says the two “spoke about Brexit and a range of other issues – including Iran, Hong Kong and 5G” network security.

Bolton told reporters afterward that a piecemeal approach to trade negotiations is “not unprecedented” and talks between the U.S. and the U.K. could concentrate first on areas where the two sides agree.

He said: “I think here we see the importance and urgency of doing as much as we can agree on as rapidly as possible.”

Britain is preparing to leave the European Union on Oct. 31.