Three Baltic states vowed on Tuesday to join forces with four other eastern EU states in seeking a compromise on tough proposals by France to overhaul a controversial EU rule on cheap labour, especially regarding the transport sector.

"We will not agree to the introduction of rules that would in practise eliminate transport companies from the countries of our region from the EU's common market," Polish Prime Minister Beata Szydlo told reporters in Warsaw alongside her Latvian and Lithuanian counterparts and a senior Estonian diplomat.

"We are counting on being able to reach a compromise, thanks to the involvement of the Estonian EU presidency, that takes into account the interests of entrepreneurs from our region," Szydlo added.

Lithuanian Prime Minister Saulius Skvernelis echoed Szydlo, insisting that "the rules of the Posted Workers Directive, and any future limitations, cannot apply to the transport sector".

"We will not agree to one-sided initiatives or proposals on the transport sector," he added.

French President Emmanuel Macron made overhauling the so-called Posted Workers Directive one of his key election promises and is set to push for it at an EU summit on October 19-20.

The regulation lets firms send workers from low-wage countries to wealthier economies on short-term assignments without paying their hosts' social charges.

The rule has caused resentment in western countries like France, Germany and Austria, which argue it amounts to "social dumping" and creates unfair competition on national labour markets.

But there has been staunch resistance in eastern and central Europe, where most of the cheap labour comes from.

Working together in the so-called Visegrad Group, the Czech Republic, Hungary, Poland and Slovakia insist that France's proposals go too far and will undercut their interests. 

Poland -- the EU member that benefits most from the regulation -- wants to keep its current rules largely intact.

An estimated 500,000 of Polish nationals are employed by Polish companies in other EU member states.

Macron and Szydlo traded harsh verbal blows last month over the posted workers reforms.

Macron, a liberal centrist, accused Poland of being a country "that has decided to go against European interests in many areas" pointing to a string of controversial reforms by Szydlo's right-wing government.

Szydlo hit back, saying that "perhaps (Macron's) arrogant comments result from lack of political experience, which I can understand, but I expect that he will make up for this shortcoming and will be more restrained in the future".