MOSCOW, June 21 (Reuters) - The Kremlin on Monday said a constructive summit between President Vladimir Putin and his U.S. counterpart Joe Biden last week had not stopped Washington from trying to contain Russia, and that having pragmatic relations was most important.

U.S. National Security Adviser Jake Sullivan told CNN on Sunday the United States was "preparing another package of sanctions" related to the use of a chemical agent against "one of their citizens on Russian soil".

Kremlin critic Alexei Navalny was flown to Germany in August last year after being poisoned with what German doctors said was the Soviet-era military-grade nerve agent Novichok. Russian authorities have repeatedly denied any wrongdoing. (Reporting by Gleb Stolyarov; Writing by Alexander Marrow; Editing by Kevin Liffey)