Cape Town - Speaker Baleka Mbete on Tuesday urged EFF leader Julius Malema to desist from using President Jacob Zuma's State of the Nation address next month to demand that he answers questions on the Nkandla controversy.Mbete wrote to Malema in response to a letter in which he threatened to "insist" that Zuma answers his party's questions at the opening of Parliament on 12 February, if she failed to convene a special sitting devoted to presidential question time beforehand."I would urge you to desist from such conduct and instead engage constructively in processing matters relating to the functioning of the [National] Assembly," Mbete wrote.She said Zuma would have an opportunity to respond to issues raised by MPs during the parliamentary debate on his address in the days thereafter.The speaker added: "The State of the Nation address on 12 February 2015 is not the appropriate forum or occasion for a question session of the National Assembly."The opposition has lambasted Zuma for failing to return to the National Assembly to answer questions after a session ended in pandemonium on 21 August when the EFF chanted "pay back the money" at the president in reference to state funds misspent on his private home in KwaZulu-Natal.In December, after he and other EFF were suspended from Parliament over that incident, Malema vowed that his party would take Zuma to task over Nkandla at the opening of Parliament.In her letter, Mbete blamed the EFF for Zuma's failure to conclude the question session, saying: "He was prevented from completing the session due to disruptions in the House."She added that scheduling a question session was the responsibility of the National Assembly Programme Committee, and said her office was in consultation with it regarding the matter of questions to Zuma.Late last year, Deputy President Cyril Ramaphosa tried to broker a detente with the opposition, which would have seen the suspension of EFF MPs put on hold. Its terms included a demand that the opposition treat the president with greater respect, but it fell apart after only one day.