* Kiev airport extends closure to 1800 GMT
* Belarus still operating some flights east and south
(Updates with Kiev closure extension, Belarus visa offer)
MINSK/KIEV, April 17 (Reuters) - Belarus restricted its airspace on Saturday and airports in Ukraine including the capital Kiev closed to flights because of the huge volcanic ash cloud drifting over Europe.
Belarus closed its airspace overnight to flights at altitudes between 6,000 and 11,000 metres, but some routes east and south were open, the head of the aviation security department, Vladimir Nagulevich, told Reuters.
Ukraine’s Aerosvit airline said the main Kiev airport would remain closed until at least 1800 GMT and possibly into Sunday.
Ukraine’s Lvov, Odessa, Donetsk, Simferopol and Dnepropetrovsk airports were also closed to flights for an unspecified period.
Europe’s air travel chaos deepened on Saturday as the huge cloud of volcanic ash from Iceland spread further across the continent, halting nearly three in four flights and stranding passengers worldwide.
Authorities in Belarus said they were offering to waive visa requirements for European Union citizens stranded in Russia and willing to return to the EU by road or rail through Belarus. (Reporting by Yuri Kulikov in Kiev and Andrei Makhovsky in Minsk; Writing by Matt Robinson in Moscow; editing by Tim Pearce)