* Opposition controls enough seats to remove Kuczynski from office
* Kuczynski aware he likely will not survive, gov't source says
* Vice President Martin Vizcarra would replace Kuczynski if ousted (Recasts after motion for presidential vacancy was approved)
LIMA, Dec 15 (Reuters) - President Pedro Pablo Kuczynski's chances of surviving the political crisis gripping Peru faded on Friday after Congress passed a motion to start "presidential vacancy" procedures with enough votes to unseat him within a week.
The opposition-controlled Congress voted 93-17 on Friday to seek his removal from office over graft allegations, which he denies. Eighty-seven votes will be needed to oust him in a session scheduled for Dec. 21, when he will be asked to defend himself.
A Brazilian construction company at the center of Latin America's biggest graft scandal disclosed this week payments totaling $4.8 million to companies owned by Kuczynski or a close friend, triggering calls for him to resign.
Kuczynski had previously denied any links to the Brazilian company, Odebrecht, and said on Thursday there was nothing improper about the payments. Flanked by his Cabinet, Kuczynski vowed not to resign in a defiant message to the nation.
However, Kuczynski was aware his chances of surviving the scandal were slim, said a government source who asked not be identified. By resisting calls to step down, he hopes to clear his name and defend due process as the Odebrecht graft investigation widens, the source said.
"This is a national disgrace," said opposition lawmaker Lourdes Alcorta. "The less harmful option for Peru would be his resignation. He's forcing us to impeach him."
Odebrecht has rocked politics in Latin America since agreeing a year ago to provide details on bribery schemes across the region - landing elites in jail from Colombia to the Dominican Republic and nearly toppling a president in Brazil.
Two former presidents in Peru, Ollanta Humala and Alejandro Toledo, have been ensnared in the Odebrecht probe over alleged payments they deny. Humala was jailed pending trial in July and authorities are seeking Toledo's extradition from the United States.
Opposition leader Keiko Fujimori, whom Kuczynski unexpectedly defeated in last year's presidential election, is also under investigation and denies wrongdoing.
If Kuczynski is forced out, he would be replaced by First Vice President Martin Vizcarra, a former governor of a copper-rich mining region and Peru's current ambassador to Canada.
Kuczynski was once lauded by many as a brilliant technocrat who would help uproot widespread corruption in Peru. But his 16 months in office have been marked by clashes with the right-wing opposition party that controls Congress.
Kuczynski said late on Thursday he was the owner, but not the manager, of a company paid by Odebrecht while he held senior government posts. He also acknowledged providing financial services for an Odebrecht project as a consultant for a friend's firm when he did not hold public office.
The opposition slammed the explanation as too little, too late. "It's really unfortunate that President Kuczynski has put the country in this situation," said congresswoman Cecilia Chacon. (Reporting by Marco Aquino and Mitra Taj; Editing by Rosalba O'Brien, Andrew Hay and Paul Tait)