The Cambodian government is convinced that two life-size 10th-century statues that have anchored the Metropolitan Museum of Art’s Southeast Asian galleries for nearly two decades were looted from a jungle temple and plans to ask for their return.


“The government is very serious about moving this forward, and we are getting much legal advice,” said Im Sokrithy, a director of Apsara, the Cambodian agency that oversees heritage and land management at the sprawling temple complex where, archaeologists say, the statues stood for centuries. “We are taking a forceful position, and we hope they can be returned.”


The twin sandstone figures, called the Kneeling Attendants, flank the doorway of the gallery where the Met displays its small but globally significant collection of artifacts from the glory days of Khmer civilization.


Experts say they appear to have been taken around 1970, at about the same time as a companion piece, a mythic warrior figure that the United States government sought to seize last month on Cambodia’s behalf from Sotheby’s, where it had been placed for sale.


Both cases illustrate Cambodia’s growing interest in restoring its cultural heritage, but the debate is somewhat different when a contested artifact is held by a museum rather than a private collector or auction house. Many in the museum world and beyond have argued that the higher profiles, larger audiences and advanced security systems at some institutions make them more appropriate places to house cherished artifacts and ensure they are available for worldwide study and appreciation.


The Met has previously returned a Khmer item, a 10th-century Shiva head that was given to Mr. Im’s agency in 1997 at the urging of Martin Lerner, the Met’s Southeast Asian curator at the time.


Anne LeMaistre, the Unesco representative in Phnom Penh, Cambodia’s capital, said her agency is assembling a report laying out evidence that the Met statues and the Sotheby’s warrior belonged to a 12-statue Khmer empire grouping first broken up when Cambodia was destabilized by civil war.


The Met, which was given the statues by benefactors in four pieces between 1987 and 1992, said it has not been contacted by Cambodia and has no information to suggest the works were stolen. The museum acknowledged that beyond the names of the donors it has no records on the statues’ origins, despite a longstanding policy to investigate the history of donated antiquities.


“No one is concealing anything,” said Harold Holzer, the Met’s senior vice president for external affairs. “I’d like nothing better that to find more documentation.”


Mr. Holzer cautioned against using current standards for museum collecting to evaluate the propriety of acquisitions dating back more than two decades. “There were no real prevailing restrictions against accepting these works of art,” he said of the period, “especially if, by doing so, they might be protected from disappearance completely from public view and from study.”


The Met’s policy in 1992 allowed it to accept works without a detailed provenance. Such acceptance, though, was supposed to come after an effort had been made to root out the history of a piece in case it was illicit. In recent years, as countries have increasingly sought to protect their cultural heritage, the Met and other museums have adopted a stricter policy. It discourages the acceptance of antiquities like the Kneeling Attendants if they lack a documented history showing they left their country of origin before 1970.


In the wake of the Sotheby’s case Cambodian officials have formed a task force to return artifacts removed from their country and possibly held by American and other foreign museums.


Prak Sonnara, deputy director general for cultural heritage with Cambodia’s Ministry of Culture and Fine Arts, said that once the government has compiled evidence to convince the Met of the validity of its claim, he would ask for the statues back “on behalf of the people of Cambodia.”


Mr. Lerner, who was the Met’s Southeast Asian curator from 1972 to 2004, said he could not recall what was done to research the provenance of the attendant statues. He said that contacting the Cambodian government by letter of inquiry — as prescribed in rules laid down in 1971 by a former Met director, Thomas Hoving — was not an option at the time of the gifts.


“Basically there was no government to send it to at the time,” he said. “It was all in a state of disarray at the time.”


Mr. Holzer said the policy of sending such letters was discontinued years ago — he could not say exactly when — because they drew a response so infrequently.