Scientific experts have greenlighted the restart of two Belgian nuclear power plants despite signs of micro-cracks in reactor vessels, the daily Le Soir said Saturday.

No independent confirmation was immediately available from Belgium's nuclear safety authority, AFCN.

Le Soir, which did not identify its sources, said "experts on material resistance who were asked for their opinion on the fate of the Tihange 2 and Doel 3 vessels have handed in a positive report."

AFCN had said it would hand the government a report on whether to restart the reactors in mid-January. It has already received a positive report from the country's Electrabel power utility.

Le Soir said the experts had however asked for "more intensive" checks.

Many "potential cracks" were found during inspections early last year at the base of the reactor vessel at Doel 3, near the northern city of Antwerp, which was closed in June, as well as at Tihange 2, near the southern city of Liege.

It was halted in August for investigation after the problems at Doel came to light.

The reactor vessels, housing the nuclear core, were built in the 1970s by the Dutch firm Rotterdamsche Droogdok Maatschappij (RDM), which has since ceased business.

RDM equipped some 20 nuclear plants, half of them in Europe.

Earlier this year, the Belgian nuclear regulator said the problems in the Doel 3 reactor likely dated back to its construction and while there was little risk for the present, there was "a malaise given the large number" of defects.

The 2011 Fukushima nuclear disaster in Japan has increased sensitivity over the safety of nuclear energy, with Germany deciding to phase out its plants.

The EU counts 147 reactors in 14 countries, with more than a third of the total in France which depends almost entirely on nuclear generators for electricity.