Switzerland has refused to reopen long-running corruption cases against Pakistani President Asif Ali Zardari as he enjoys immunity as head of state, Pakistan's law ministry said on Sunday.
The development could draw a line under a three-year row that has pitted Pakistan's top court against the ruling Pakistan People's Party (PPP), cost a prime minister his job and threatened to bring down the government before the end of its term.
Pakistan wrote to Swiss authorities in October over the multi-million-dollar allegations against Zardari, which date back to the 1990s, at the insistence of the country's Supreme Court.
Zardari and his late wife, former premier Benazir Bhutto, were accused of using Swiss banks to launder $12 million in alleged kickbacks.
Yasmin Abbasey, the top official in the law ministry, told AFP on Sunday that the Swiss had replied saying they would not reopen the cases, which were frozen when Zardari became head of state in 2008.
"They have responded to the letter and said the president has immunity," she said.
"This was the main issue and they have confirmed it that the president enjoys immunity."
Pakistan's top court spent nearly three years demanding the coalition government, led by Zardari's PPP, ask the Swiss to reopen the cases before the politicians finally relented.
The tussle cost prime minister Yousuf Raza Gilani his job in June last year, when the Supreme Court convicted him of contempt for refusing to obey its orders to write to the Swiss, forcing him out of office.
Critics argued the Supreme Court's dogged pursuit of the Swiss cases amounted to a political crusade against the PPP's coalition government, and the case has contributed to political instability in the restive, nuclear-armed state.
After Gilani's removal as prime minister there were fears his successor Raja Pervez Ashraf could suffer the same fate, and the government could fall before completing its five-year term in March.
As far back as March 2010, Swiss prosecutors pointed out that it was impossible to reopen the cases against Zardari while he was president.
The PPP is facing a tough fight in the general election, which is expected in the coming months, and should they lose the possibility arises that Zardari may lose the presidency -- and his immunity from prosecution.