Ukrainian lawmakers announced a bill on Wednesday that would allow businesses to exempt their employees from military service if they pay a $500 monthly fee per worker.

Hundreds of thousands of draft-age men have left or stayed outside of Ukraine since the war began in 2022, with almost three quarters of companies experiencing staff shortages partly as a result, according to a survey published in April.

"In these times, the functioning of any business depends on predictability, and the first question that worries most manufacturers today is whether they will be able to retain critical employees," ruling party MP Dmytro Natalukha said on Facebook.

According to the bill, "every business entity that pays the increased military fee of 20,000 hryvnia ($500) per month per employee" will have the opportunity to "reserve" that worker, Natalukha said.

"The increased fee is paid not by the employee, but by the business itself," Natalukha said, adding that businesses would decide for themselves "who is most critical".

The bill came about after dialogue with both government officials and business and will help Kyiv ensure the "continuous and predictable" running of its companies, Natalukha said.

The debate surrounding mobilisation is extremely sensitive in Ukraine, which has been unable to give its long-serving conscripts a break as it suffers from acute troop shortages on the front.

Authorities have introduced a string of measures designed to boost the war effort, including allowing some prisoners to fight, lowering the draft age to 25 and toughening penalties on draft-dodgers.

Officials said last week that draft-age Ukrainian men with permanent residency in other countries would in most cases no longer be able to leave the country if they visited Ukraine.