A lesbian couple married in Massachusetts should have the same right as heterosexual couples to now divorce in Rhode Island, lawyers for the women told the state's highest court on Tuesday.

Cassandra Ormiston and Margaret Chambers wed in 2004 soon after Massachusetts legalized same-sex marriages. They filed for divorce last year in their home state of Rhode Island, where the law is silent on whether same-sex marriages are legal.

It is believed to be the state's first same-sex divorce case.

If the women can't divorce in Rhode Island, their lawyers said the only legal avenue available to them would be for at least one to move to Massachusetts and live there long enough to obtain a divorce.

"It is an absolutely unfair burden," Ormiston said outside court after Tuesday's arguments before the Rhode Island Supreme Court. "It is a burden no one else is asked to bear, and it is something I will not do."

Lawyers for the women told the Supreme Court the only question to consider was whether Rhode Island could recognize a valid same-sex marriage from another state for the sole purpose of granting a divorce petition.

They stressed the case has no bearing on whether gay couples could get married in Rhode Island, or on whether a same-sex marriage would be recognized for other purposes.

"You have a valid marriage in the state of Massachusetts," Louis Pulner, an attorney for Chambers, told the justices. "No one is asking the court to address the question of whether such marriages would be valid in Rhode Island."

In September 2006, a Massachusetts judge decided same-sex couples from Rhode Island could marry in Massachusetts because nothing in Rhode Island law specifically banned gay marriage. But the courts and the legislature in Rhode Island have not taken any action to recognize same-sex marriages performed in Massachusetts.

Attorney General Patrick Lynch earlier this year issued a nonbinding advisory opinion saying the state would recognize same-sex marriages performed in Massachusetts.

Nancy Palmisciano, a lawyer for Ormiston, said Rhode Island routinely treats as valid heterosexual marriages performed in other states and even in other countries. She said when she recently handled the divorce of a couple from China, no one questioned the validity of their marriage certificate issued there.

"Here we have two American women who have not been able to push their divorce forward because they happen to be members of the same sex," Palmisciano said.

Chambers and Ormiston married in Fall River, Mass., in May 2004 in a ceremony solemnized by a justice of the peace. Massachusetts is the only state to legalize same-sex marriages.

Chambers filed for a divorce last October, citing irreconcilable differences.

Two months later, Rhode Island's chief family court judge asked the state Supreme Court for guidance on whether he has the authority to handle a same-sex divorce. The court agreed to weigh in and invited Rhode Island's legislative leaders, governor and state attorney general to submit legal briefs detailing their position.

The justices did not indicate when they would rule.