Ukraine has relinquished its ambition of joining the NATO military alliance in exchange for Western security guarantees as a compromise to end the war with Russia, President Volodymyr Zelenskyy said ahead of talks with U.S. envoys in Berlin.

A Republican congressman has introduced legislation calling for the U.S. to withdraw from NATO. The bill, introduced by Representative Thomas Massie of Kentucky and co-sponsored by Representative Anna Paulina Luna of Florida, seeks to "remove the United States" from the alliance it has spearheaded since its inception in 1949.

GOP Rep. Thomas Massie fielded a bill to remove the U.S. from NATO, putting forward a companion measure after Sen. Mike Lee introduced a bill earlier this year.

NATO chief Mark Rutte has warned that Russia is escalating its covert campaign, as an expert outlines a chilling three-stage scenario of what conflict could look like in Britain.

Former Swedish Foreign Minister Tobias Billström said after the Ukraine war, Europe must be ready for further Russian aggression.

Rep. Thomas Massie (R-Ky.) on Wednesday introduced a bill that would pull the United States out of the NATO alliance. Rep. Anna Paulina Luna (R-Fla.) said she would co-sponsor the bill, while Sen. Mike Lee (R-Utah) has introduced companion legislation in the upper chamber.