Myanmar's junta chief warned political parties to behave while campaigning forhistoric elections later this year. He also said, today that the armed forces can take part in politics whenever the need arises.In his annual national address, Senior Gen. Than Shwe maintained his silence on when Myanmar's first election in two decades will actually take place.No date has been announced for the upcoming polls, which critics have called a sham designed to keep the military in power with the facade of an elected government. The 77-year-old Than Shwe's seven-minute speech focused on the elections and the role of the army. He warned political parties to be courteous.He reiterated concerns that foreign countries might seek to interfere in the elections – usually a reference to Western countries. Myanmar has been under military rule since 1962.The polls will be the first since 1990, when the opposition party led by Aung San Suu Kyi won a landslide victory. The junta ignored the results of that vote and has kept the Nobel Peace laureate jailed or under detention for 14 of the past 20 years.The junta recently enacted five electoral laws widely criticised as designed to keep Suu Kyi out of the race. One of the laws prohibits anyone convicted of a crime from being amember of a political party, and instructs parties to expel convicted members or face de-registration. Speaking through her lawyers, Suu Kyi called the laws "unjust" earlier this week and said she would "not even think" of taking part in elections, but she will let her NationalLeague for Democracy party decide for itself.The NLD plans to meet Monday to decide if it will register for the elections.