The company, currently in the focus of Russian tax authorities, has audited Gazprom since 1995.
Gazprom said the audit contract would be clinched after approval by the annual shareholders' meeting scheduled for June 29.
On March 20, the Moscow Arbitration Court annulled a contract between bankrupt oil company Yukos and PwC, its auditor in 2002-2004, which has been accused of covering up the company's tax shelter schemes and drawing up two different audit reports over three years. The court also ordered PwC to pay the state $480,000.
PwC said it would appeal against a court ruling invalidating the audit contract, which it said was unsubstantiated and based on a fundamentally different understanding of an auditor's role and functions.
Investigators from the Russian Interior Ministry and the Prosecutor General's Office last month raided PwC's Moscow office and seized documents. They suspect PwC of evading 243 million rubles ($9.3 million) in taxes in 2002.
The company protested the seizure, saying the documents had nothing to do with 2002 tax claims, and that it had already paid all tax arrears. Russian law enforcement pressed the 2002 profit tax claim against PwC a year ago.
The company has lost three appeals in arbitration courts since then, and said it was considering an appeal to the Supreme Arbitration Court.
Russian tax authorities are accusing PwC's Moscow branch of underreporting profit tax on sums it allegedly paid to offshore PricewaterhouseCoopers Resources B.V., which was supposed to provide financial consultations to clients in Russia. Tax officials said the consultation services were provided by the company's Moscow branch instead.
