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The wife of a California man detained in Vietnam since July has been invited by her congresswoman to attend President Donald Trump’s State of the Union on Tuesday.

Rep. Katie Porter, D-Calif., said in a statement that Helen Nguyen's husband, Michael Phuong Minh Nguyen, has been held in a detention center in Ho Chi Minh City for nearly seven months without any formal charges being brought, Porter said in a statement.

“The continued detention of an American citizen without charge is unacceptable,” Porter, who took office last month, said. “Michael Nguyen needs to return home as soon as possible to his family in Orange County.”

Michael Nguyen with his family. Courtesy Nguyen Family

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A U.S. citizen who was born in Vietnam, Michael Nguyen was detained on July 7 on his way to Ho Chi Minh City from Da Nang, Vietnam, according to a statement from the family last year. His family said he was under investigation by the Vietnamese for “activity against the people’s government."

Nguyen, a father of four, left California in late June to visit friends and family in Vietnam, his brother-in-law, Mark Roberts, told NBC News last summer. Roberts added that Nguyen, who owns a small print shop, did not appear to be involved in any political activity.

Since his detention, the Nguyens have lost their business, and the ordeal has created enormous stress for Helen Nguyen and their children, Porter said in her statement.

“She has essentially been a single mom with four school-aged daughters for nearly seven months, while she works two jobs as a nurse to support their family,” Porter said.

The statement said Nguyen has not been permitted to contact his family since being detained, though he receives visits from a U.S. State Department consular officer once a month.

The State Department did not immediately respond to a request for comment, but Porter’s office said the department reported that Nguyen is healthy.

Nguyen’s detention came on the heels of another U.S. citizen of Vietnamese descent being taken into custody in June after participating in a protest in Vietnam. In that case, Will Nguyen (no relation to Michael) was convicted by a Vietnamese court and ordered to be deported from the country.

It is unclear whether the detention of U.S. citizens in Vietnam will make it into Trump’s address on Tuesday night, which is expected to focus on five main topics: immigration, U.S. trade relationships, new infrastructure spending, lowering health care costs, and foreign policy, such as the president's plans to withdraw troops from Afghanistan and Syria.

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