Belarus has filed a formal protest with the U.S. ambassador to the country against U.S. financial sanctions imposed on Belarusian oil processor Belneftekhim.

The Foreign Ministry says it presented U.S. Ambassador Karen Stuart with a note Thursday protesting what it called the violation by Washington of an existing trade agreement.

The United States on Tuesday prohibited Americans from doing business with the state-owned Belarusian oil processor. The action against the Belarusian State Concern for Oil and Chemistry extends to its offices in Germany, Latvia, Ukraine, Russia and China.

The sanctions also freeze any assets the oil monopoly has under U.S. jurisdiction, including the wholly-owned U.S. subsidiary, Belneftekhim, USA.

Alexander Lukashenko

The sanctions stem from a 2006 executive order from President Bush aimed at isolating authoritarian President Alexander Lukashenko. Mr. Bush has repeatedly referred to him as Europe's last dictator.

The United States and the European Union accuse Mr. Lukashenko of jailing his opponents and members of independent news organizations. Western governments also accuse the Belarusian leader of vote-rigging in his 2006 re-election to a third term.

Some information for this report was provided by Reuters.