WARSAW, Poland — A former Polish president, Lech Walesa, in a new book released just three weeks before snap parliamentary elections, says the twin brothers now governing Poland have ruined the country “in a ruthless manner.”

Mr. Walesa, 64, an electrician from the Lenin Shipyards in Gdansk who rose to power as the leader of the Solidarity movement that toppled Poland’s communist regime in 1989, said he wrote “My Third Republic: I Lost My Patience” in response to the bumbling of the prime minister, Jaroslaw Kaczynski, and the president, Lech Kaczynski.

“I can’t remain silent when our country is being ruined in a ruthless manner,” Mr. Walesa, a Nobel Peace Prize laureate, writes in the introduction. “I can’t stand the ridicule of Poland on the international stage, condemning it to isolation by the pettiness and complexes of the governing team.”

The Kaczynskis’ socially conservative Law and Justice Party swept to power in October 2005, but their tenure has been marked by instability, frequent feuds with neighboring countries and Brussels, and insider fighting amid attempts to hold on to a fragile majority with the help of two smaller anti-E.U. parties.

Last month, the Parliament voted to dissolve, triggering early elections scheduled for October 21. The Kaczynski brothers were once close associates of Mr. Walesa in the anti-communist Solidarity movement. But Mr. Walesa and the twins had a fierce falling-out in the early 1990s, when Mr. Walesa was Poland’s president.

Mr. Walesa said he was also driven by the twins’ portrayal of the past 18 years — including his own 1990–1995 term as president — as a period of betrayal rife with corruption.

“I travel around the world and am ashamed of what’s going on in Poland,” Mr. Walesa said during a packed signing of the book — his first in 16 years — at Warsaw University Library.