Amendments to Ukraine's constitution should be decided with a national referendum, Prime Minister Arseniy Yatsenyuk said amid mounting international pressure to push through controversial changes in the West-leaning former Soviet republic and enable a settlement of the conflict in its eastern regions.

"It is time for the Ukrainian people to say what should be Ukraine's new constitution in new European Ukraine. No one but the people of Ukraine has the right to determine the fundamental law," Yatsenyuk said on January 24 on the Ukrainian TV programme "10 minutes with the Prime Minister".

Yatsenyuk's call comes as Ukraine's backers, including the United States, step up pressure on Kyiv to amend the constitution, in part to end the insurgency in the eastern Donbas, which has Moscow's support in its quest for more autonomy.

The proposed changes would provide some rights of self-government to Ukraine's regions, including separatist-held territories in the mainly Russian-speaking East. In August 2015, the Ukrainian parliament adopted the disputed decentralisation law in the first reading, despite fierce opposition from Ukrainian nationalist groups. 

"The new constitution means a new social contract between citizens and the authorities which they have elected. The contract on the distribution of rights and responsibilities within the governing bodies – between the president, the government and the parliament," Yatsenyuk added.

Frozen conflict warning

Meanwhile, Ukrainian President Petro Poroshenko has sent mixed signals by saying decentralisation and constitutional amendments exclude the adoption of laws on a "special status" of any regions of Ukraine. 

"On the contrary, decentralisation and constitutional amendments relieve from any thoughts of creating laws on 'special status' of certain cities, regions and territories," UNIAN news agency quoted Poroshenko as telling a conference of representatives of local authorities in Kyiv on January 23.

At the same time, he warned against "games with fire" involving Ukraine's territorial integrity. "The logic of the Minsk process ensures the restoration of sovereignty of the Ukrainian Donbas," Poroshenko's media office quoted him as saying.

The president also warned against a freezing of the conflict in the country's eastern industrial heartland. "We do not have any examples of return of 'frozen' territories. Didn't we learn anything from the experience of Abkhazia, South Ossetia, Nagorno-Karabakh, Transnistria? Each year of frozen conflict distances us from the return of sovereignty," Poroshenko underlined.

Preconditions on the table

On January 24, Poroshenko said in an interview with Ukrainian TV channels that several important preconditions, first of all ceasefire and a long period of silence, must precede the approval of constitutional amendments on decentralisation.

"Russia must ensure this and the world must see that this is happening," Poroshenko said. Another key task, according to the president, is to ensure access to the weapons storage sites for the the Organisation for Security and Cooperation in Europe (OSCE), as well as restore control over the Ukrainian-Russian border by the OSCE at the first stage.

Zenon Zawada the Concorde Capital brokerage in Kyiv believes that if the constitutional amendments must truly correspond with progress in resolving the Donbas war, "it's doubtful they will ever be brought to a vote". The amendments need to secure at least 300 votes of lawmakers in Ukraine's 450-seat parliament in the second reading under requirements for a so-called "constitutional majority". 

More importantly, Yatsenyuk's call for a referendum makes the amendments' approval even more unrealistic, Zawada said.

Meanwhile, possible inability of securing 300 votes of lawmakers could potentially trigger snap parliamentary elections, local media reported. According to Ukraine's 112 TV channel, if the required number of votes for the bill are not collected, there is a probability of dissolving the parliament and holding early elections, which would be scheduled for the autumn.

"The task is to hold out until the US presidential election.After that, the situation with the implementation of the Minsk agreements will chnage in any case," the channel quoted unnamed official source in Kyiv as saying.

"There are no 300 traitors"

Meanwhile, Oleh Liashko, the head of the Radical party, announced on January 25 that the national authorities do not have 300 votes of lawmakers to secure the changes. According to the politician, his party alongside the Batkivschyna (Fatherland) party, headed by former prime minister Yulia Tymoshenko, and the Samopomich (Self Reliance) party, headed by the mayor of the western city of Lviv Andriy Sadovyi, fiercely oppose the proposed changes to the constitution.

"Thank God, there are not 300 traitors in parliament," the Ukrainskaya Pravda news portal quoted Liashko as saying. He also called for a national referendum in March on the status of the Donbas, de facto supporting Yatsenyuk's proposal, a turn of events which could sorely disappoint Ukraine's Western backers.

Moscow's game plan in the current turmoil is to try and expose Kyiv "for failing to meet its commitments to Minsk II [agreement], and as a result to secure the erosion of support in the European Union and West for the maintenance of sanctions", commented Timothy Ash, a strategist with Nomura International.