EU dangles carrot for wayward Ukraine leader

With the treaty also needing to be ratified by all 27 member states' administrations, the Union added that it could already enter into life on a "provisional" basis as soon as the signing takes place.

"The signature could be accompanied by opening for provisional application of parts of the agreement," the EU foreign ministers said.

The EU offer is designed as an incentive for President Viktor Yanukovych to mend his ways after his last two years in power saw backsliding on democratic standards and corruption.

The ministers' statement did not name Yulia Tymoshenko or Yuriy Lutsenko - leading opposition figures jailed by Yanukovych in what the EU has dubbed as politically motivated trials.

But it warned that the treaty signature will not go ahead unless Ukraine meets strict conditions.

"[The EU] expects the authorities to address the cases of politically motivated convictions without delay as well as to take further steps to reform the judiciary to prevent any recurrence," the ministers said.

They also listed compliance with international parliamentary election standards and close co-operation with the Strasbourg-based human rights watch dog, the Council of Europe, on new laws addressing the role of the prosecutor's office and the high council of justice.

Ukraine will also have to revamp its criminal codes, reform the police and review laws on the judicial system and the status of judges, the ministers said.

For its part, the Tymoshenko camp has in the past called for EU sanctions on the main protagonists in her jailing.

EU diplomats say that sanctions are not under consideration.

But the US has banned Ukraine's deputy prosecutor general Renat Kuzmin from entering into US territory, AFP reports.

Kuzmin, a key figure in the case against Tymoshenko, said on Monday he had been informed by US ambassador John Tefft that his visa was cancelled but "without further explanation."

Kuzmin had entered the US over the summer to conduct further investigations on Tymoshenko but had not informed or co-ordinated his work with US authorities.

The decision to revoke his visa may also stem from a US resolution passed in September to revoke visas on anyone involved in jailing the opposition leader.