Bolivia signed a $300 million deal with Russia on Sunday to build a world-class nuclear research lab in the South American nation, President Evo Morales announced.

"Now we are able to deliver major cooperative projects -- in this case with Russia as well as with China and Europe sometimes," the president said at a ceremony signing documents for the deal.

"How nice that some partners come here with investment and cooperation -- not just aggression and provocation," Morales said in an apparent jab at the Unites States, which he often accuses of undermining efforts of his leftist government.

Work on the Russian technology plant in El Alto, next to the capital, is expected to take four years.

It is due to include components on medical research, food safety and nuclear research "with non-violent ends."

A new state agency will be in charge of the lab project.

Last month, a massive referendum defeat was Morales's first direct election loss since taking office a decade ago.

It means he will have to step down at the end of his current mandate, in 2020.

Morales, 56, is already Bolivia's longest-serving leader since independence from Spain in 1825.