Ukraine is preparing to stage a military parade next month to mark 30 years of independence following the Soviet Union's breakup, and the defence ministry released photographs of fatigue-clad women soldiers marching in mid-heel black pumps.

"Today, for the first time, training takes place in heeled shoes," cadet Ivanna Medvid was quoted as saying by the defence ministry's information site ArmiaInform.

"It is slightly harder than in army boots but we are trying," Medvid added in comments released on Thursday.

The choice of footwear sparked a torrent of criticism on social media and in parliament, and led to accusations that women soldiers had been sexualised.

"The story of a parade in heels is a real disgrace," commentator Vitaly Portnikov said on Facebook, arguing that some Ukrainian officials had a "medieval" mindset.

Another commentator, Maria Shapranova, accused the defence ministry of "sexism and misogyny."

"High heels is a mockery of women imposed by the beauty industry," she fumed.

Several Ukrainian lawmakers close to Ukraine's former president Petro Poroshenko showed up in parliament with pairs of shoes and encouraged the defence minister to wear high heels to the parade.

"It is hard to imagine a more idiotic, harmful idea," said Inna Sovsun, a member of the Golos party, pointing to health risks.

She also said that Ukraine's women soldiers -- like men -- were risking their lives and "do not deserve to be mocked".

Ukraine has been battling Russian-backed separatists in the country's industrial east, in a conflict that has killed more than 13,000 people since 2014.

Olena Kondratyuk, deputy speaker of the legislature said authorities should publicly apologise for "humiliating" women and conduct an enquiry.

Kondratyuk said that more than 13,500 women had fought in the current conflict.

More than 31,000 women now serve in the Ukrainian armed forces, including more than 4,000 of whom are officers.