The Soviet Union, once branded an "evil empire" by former President Reagan, is fast becoming an "irrelevant empire," largely because of its economic weakness, says ex-President Richard Nixon.

"Reagan was lambasted for calling the Soviet Union an evil empire. Today it is becoming an irrelevant empire," Nixon says in the magazine U.S. News and World Report.Nixon, the only president to resign from office, has just ended a two-week visit to the Soviet Union that included talks with Soviet President Mikhail Gorbachev and Russian Republic leader Boris Yeltsin and visits to three separatist republics: Lithuania, the Ukraine and Georgia.

"In today's world, an empire that has only military power and is a Third World economic power, falling hopelessly behind, will eventually become irrelevant," Nixon said.

The ex-president said the Soviet economic crisis is so severe that it is diminishing the importance of concluding a strategic arms agreement with Moscow, an accord long sought by the Bush administration.

"In view of the enormous economic problems the Soviet Union has, the need for a treaty is not as great. They are not going to be able to afford the expenditures necessary for military modernization," Nixon said.