A European rights watchdog ruled on Friday that Ukraine's new law requiring state schools teach older children almost entirely in Ukrainian might be discriminatory.

The explosive legislation has poisoned Ukraine's ties with neighbours Romania and Hungary in particular -- which both have sizable minorities in Ukraine.

Much of Ukraine's southeast is Russian-speaking so the rule has also further inflamed relations with Moscow as a nearly four-year war against Kremlin-backed insurgents rumbles on in the east.

Ukraine currently has hundreds of schools that provide lessons to ethnic minority communities in their own languages.

Kiev tried to soothe the tensions by submitting the law for review by the Venice Commission -- a Council of Europe group of constitutional law experts whose rulings member states commit to respect.

The commission said in a formal opinion on Friday that "the strong domestic and international criticism drawn especially by the provisions reducing the scope of education in minority languages seems justified".

The language law was adopted in September and is scheduled to enter into force when the school year starts in 2020.

Romanian President Klaus Iohannis cancelled a planned visit to Ukraine in protest against the law when it was adopted.

And nationalist Hungary went as far as to threaten to block Ukraine's rapprochement with the European Union.

Moscow has long complained about the alleged persecution of ethnic Russians by the pro-EU leadership that rose to power after a 2014 revolution toppled a Kremlin-backed regime.

- 'Difficult to justify' -

The new legislation allows ethnic minorities to be taught for their first four school years in their own language and to take separate Ukrainian lessons.

It requires nearly all classes to switch to Ukrainian for children from approximately the age of 10.

The law says a few subjects can be tought in one of the official EU languages but remains vague on that point.

But because Russian is not an EU language it is effectively banned from instruction for older children and the Venice Commission said this also appeared to be a problem.

"The less favourable treatment of (non-EU) languages is difficult to justify and therefore raises issues of discrimination."

The nuanced Venice Commission ruling appeared to partially side with Kiev's defence of the law and did not outright call it in contravention with Ukraine's European or international commitments.

"It is a legitimate and commendable aim for states to promote the strengthening of the state language and its command by all," the commission said.

It also urged Kiev "to amend the Education Law to provide more time for a gradual reform".

Ukraine's education ministry said it welcomed the opinion and was ready to make amendments to the law that could better accomodate ethnic minorities and allow schools more time to adjust.

"From the educational point of view, extending the transition period (past 2020) is justified and we will fully support this recommendation," the Ukrainian ministry said in a statement.

Any changes to the language law would have to be submitted for final approval to parliament and be signed by President Petro Poroshenko to take effect.

Source: AFP