U.S. President Barack Obama has reiterated his pledge to work toward comprehensive nuclear disarmament and confirmed progress in talks on a new strategic arms reduction treaty with Russia.

"I have embraced the vision of John F. Kennedy and Ronald Reagan through a strategy that reverses the spread of these weapons, and seeks a world without them," Obama said in his annual State of the Union speech on Wednesday.

"To reduce our stockpiles and launchers, while ensuring our deterrent, the United States and Russia are completing negotiations on the farthest-reaching arms control treaty in nearly two decades," he said.

A new document to replace the START 1 treaty, which expired on December 5, has not been signed yet over disagreements on verification and control arrangements to be included in the document.

Obama and Russian President Dmitry Medvedev agreed in a telephone conversation earlier on Wednesday to order the speedy completion of the deal, which is almost ready to be signed, according to officials on both sides.

The new treaty's outline, as agreed on by the Russian and U.S. presidents, includes cutting nuclear arsenals to 1,500-1,675 operational warheads and delivery vehicles to 500-1,000.

In his key political address on Wednesday Obama also urged other countries to strictly observe the nuclear non-proliferation and nuclear security regime.

"At April's Nuclear Security Summit, we will bring 44 nations together behind a clear goal -securing all vulnerable nuclear materials around the world in four years, so that they never fall into the hands of terrorists," he said.

The White House earlier said that the summit in Washington will facilitate "discussion on the nature of the [nuclear] threat and develop steps that can be taken together to secure vulnerable materials, combat nuclear smuggling and deter, detect, and disrupt attempts at nuclear terrorism."