Poland's foreign minister says the European Union could lose its global influence if it continues to delay economic decisions.

Radoslaw Sikorski told parliament on Thursday that an EU decline could create a “void” in the bloc's global influence that would most likely be filled by countries including Russia.

He said the current financial crisis gripping much of Europe could stop the growth of the EU's economy.

The Associated Press says Sikorski also told parliament that a weakened EU could prompt the United States to end its close military ties with Europe and pull out of NATO. He called for deeper integration within the 27-nation bloc.

In a separate development, the twin brother of former Polish president Lech Kaczynski says his brother's death in a 2010 plane crash is increasingly looking like an “assassination.”

A plane carrying Mr. Kaczynski crashed during a landing attempt in Russia, killing the former leader and 95 other people on board. Investigators said thick fog and pilot error caused the crash.

The president's brother, opposition leader Jaroslaw Kaczynski, has been a vocal critic of the government's handling of the crash. His comments on Thursday marked some of his strongest language yet suggesting the crash was intentional.

He called for an international investigation of the incident. Russia has denied any blame.