NAIROBI (Reuters) - Burundi's government refused on Thursday to cooperate with a U.N. inquiry into months of political violence, saying accusations of abuses by its officials were part of a political plot.

The United Nations announced the inquiry this week to identify perpetrators in the central African state, which has been riven by clashes and killings since protests erupted in 2015 against the president's decision to seek a third term.

"We are not involved in the investigation to be carried out by this commission," Burundi's human rights minister, Martin Nivyabandi, told journalists on Thursday.

"We are not refusing to cooperate with human rights institutions (on all matters) ... we will continue to cooperate on other issues but will not be part of the investigation."

The United Nations released a report by independent experts in September identifying government officials suspected of ordering political opposition to be tortured or killed.

The allegations infuriated the government, who banned the three experts from Burundi. 

Nivyabandi said on Thursday that the September report was "politically oriented" and warned "there are some international organizations whose goal is to destabilize some governments in Africa."

The International Criminal Court said in April that political violence had killed about 450 people and forced hundreds of thousands to flee.

Burundi last month began the process of withdrawing from the global tribunal which was set up to try the most serious crimes when local legal structures fail.

Opponents said President Pierre Nkurunziza's decision to seek a third term violated the constitution and the terms of a peace agreement that ended a civil war in 2005.

The opposition mostly boycotted the 2015 election and Nkurunziza won a third term.

(This story was refiled to fix typo in second paragraph so date reads 2015 not 2105)

(Writing by Katharine Houreld; Editing by Andrew Heavens)