KUALA LUMPUR, Jan 16 (AFP) - Malaysia's Mahathir Mohamad will exceed "the worst excesses" of his 19 years as prime minister during his final term since all checks to his power have been dismantled, a leading opposition figure said Sunday.

Lim Kit Siang condemned last week's crackdown on opposition figures as "the negative politics of spite, hate and vendetta" and urged "cooler heads" in government to drop criminal charges against the five, to promote national reconciliation.

The arrests and charges have drawn widespread overseas condemnation. The US State Department Friday said it shared "widely expressed concerns that these arrests are a transparent and cynical attempt to intimidate government opponents and stifle legitimate political discourse."

Lim, chairman of the Democratic Action Party (DAP), told a party meeting Malaysians had hoped that politics would become less dominated by race and religion and more by issues of "justice, freedom, democracy and good governance."

But he said events since the November 29 election, in which Mahathir's National Front (Barisan Nasional) coalition retained its two-thirds parliamentary majority, indicated otherwise.Mahathir, aged 74 and in power since 1981, has said this will be his last term.

"The final term of Mahathir as prime minister will be the most dangerous times for Malaysian national-building as all external checks and balances have been dismantled while there are no countervailing forces inside UMNO and Barisan Nasional to give him a reality check," Lim said in a speech.

The United Malays National Organisation (UMNO) is the National Front's dominant party.Lim described the arrests as a crackdown against the rule of law, press freedom and democracy.

Citing what he called a lack of accountability and transparency, the neutralising of independent bodies and the violation of human rights since 1981, Lim predicted that "the worst excesses of the Mahathir rule ... are going to be exceeded in his last term."

Charged in court Friday with sedition were Karpal Singh, counsel for deposed and jailed deputy premier Anwar Ibrahim, and Marina Yusoff, vice-president of the National Justice Party formed by Anwar's wife. Anwar's former aide Mohamad Ezam Mohamad Nor, the party's youth chief, was charged under the Official Secrets Act with possession of classified documents.

Zulkifli Sulong, editor of the Harakah newspaper owned by the opposition Parti Islam SeMalaysia, and its publisher Chia Lim They were also charged with sedition when they appeared in court Thursday.

Karpal, deputy DAP chairman, was charged in connection with a statement he made in court during Anwar's continuing sodomy trial.

Lim said Malaysia was becoming "an international pariah" by violating the United Nations' basic principles on the role of lawyers, which conferred immunity for statements made in court in good faith.

The DAP chairman also rapped the prosecution of Marina over comments which reportedly accused UMNO leaders of instigating bloody race riots in 1969. Lim urged Malaysians to lodge police complaints against government leaders whom he said had accused the opposition of instigating those riots.

Ezam, Lim said, was the first political leader to be charged under an amendment to the Official Secrets Act which provides for a mandatory minimum one-year jail term on conviction.

He said the documents which Ezam was accused of distributing to journalists -- reports by the Anti-Corruption Agency on investigations into two senior government supporters -- had been posted on the Internet for months.

The government says those arrested are accused of breaking the law and the opposition is not being targeted for any systematic crackdown.

Lim also described as "Stalinist" the decision by UMNO's Supreme Council that its two top posts should not be contested in May party elections.The council this month recommended that Mahathir and his preferred successor, Deputy Premier Abdullah Ahmad Badawi, be nominated unchallenged as party president and deputy president.