Myanmar, also called Burma, has indefinitely postponed next month's by-elections in the troubled northern state of Kachin, state media reported Friday.

Three electoral districts are affected by the delay, which government officials attributed to instability in the Kachin region.

Because of security reasons there are no conditions to hold free and fair elections, state television announced.

Fighting between rebel forces and the army in parts of Kachin state, along Myanmar's border with China, began last June. The brutal conflict, in which the army's conduct has been condemned by human rights groups, has since forced tens of thousands of people to flee their homes.

The elected, yet military-backed, civilian government of president Thein Sein has attempted to quell various uprisings since it took power last year. The government reached peace agreements with other anti-government groups, yet its attempts to broker a deal with the Kachin rebels have failed.

Western nations maintain sanctions against Myanmar, citing military brutality and human rights violations. However, President Thein has made some efforts at reforms, including the release of hundreds of political prisoners. His regime has also invited foreign monitors, including those from the US and European Union, to observe the parliamentary elections next month.

If deemed fair, the April 1 poll may prompt some Western nations to re-evaluate the sanctions on Burma.

The elections, which will occur on time in 45 other districts of Burma, will include the participation of renowned pro-democracy candidate and Nobel Peace Prize laureate Aung Suu Kyi. She visited two Kachin constituencies during the course of her campaign.

Suu Kyi's National League for Democracy (NLD) won an overwhelming victory in the 1990 elections, but the military prevented the NLD from taking power by refusing to recognize the poll results. Suu Kyi subsequently spent many years under house arrest -- she was released in 2010.

Now, the NLD says some of its candidates faced harassment by the ruling Union Solidarity and Development Party. NLF also claims certain irregularities including the presence of thousands of deceased people on voter lists, while other voters have been barred from registering, the BBC reported.

Opposition candidates also question the validity of the government's intentions in delaying elections in Kachin state.

The election is very important for the system we are building. I really regret that it won't be held at all in Kachin state, Nyan Win, Suu Kyi's campaign manager, told Agence France Presse.

I even went to villages there. There was no security problem. I think the government gave security as a reason. I don't know whether it's true, he added.

The U.S. announced Friday it is reserving judgment until the facts are made clear.

We have had concerns about the violence in Kachin, a State Department spokeswoman said. We are seeking to understand what the Burmese intentions are so that the people of Kachin are not disenfranchised.