Yangon, Aug 12 (DPA) An attorney for Myanmar opposition leader Aung San Suu Kyi said Wednesday that the Nobel Peace Prize laureate plans to appeal the guilty verdict that placed her under house detention for another 18 months, outraging the international community.

'I will try to get a certified copy of the verdict, and after I've got it, we will appeal to the Divisional Court for Daw (Mrs) Aung San Suu Kyi to overturn the guilty verdict,' lawyer Nyan Win said.

Meanwhile, authorities arrested pro-democracy activist Naw Ohn Hla as she attempted to visit Suu Kyi at Suu Kyi's Yangon home, now her prison again, witnesses said.

On Tuesday, a court set up in Yangon's Insein Prison to try Suu Kyi, her two household helpers and US national John William Yettaw found all four defendants guilty of violating the terms of Suu Kyi's previous detention at her lakeside home.

Yettaw swam to Suu Kyi's house-cum-prison May 3, staying uninvited until May 5 and providing a pretext for Myanmar's military regime to accuse Suu Kyi of violating the terms of her detention.

Yettaw, 54, has been sentenced to seven years in prison with hard labour.

The Insein Prison court initially sentenced Suu Kyi, whose previous term of house detention had been due to expire in May, and her aides to three years in prison with hard labour, but the verdict was commuted to 18 months under house detention by Myanmar's military supremo, Senior General Than Shwe.

The 18-month detention period will keep Suu Kyi out of the political picture while the regime, which has been internationally condemned for a range of human rights abuses, pushes through its plans to stage a general election some time next year, which promises to be neither free not fair.