WASHINGTON (Reuters) - The U.S. has imposed visa restrictions on senior officials at a European charter flight company for "facilitating irregular migration" through Nicaragua as the Biden administration seeks to curb what it called a growing trend.

The U.S. State Department, in a statement on Wednesday, did not name the company or its executives, or say how many migrants the company had flown into the country over what time period.

Such flights are part of a new wave of illegal immigration to the United States that the country is struggling to control. Immigration is a top issue in the Nov. 5 U.S. presidential election.

Migrants from outside Latin America pay smuggling networks hefty fees for travel packages that can include airline tickets to Central America, where they then travel by land to the U.S.-Mexico border.

"No one should profit from vulnerable migrants — not smugglers, private companies, or public officials," department spokesman Matthew Miller wrote.

"We will continue to impose visa restrictions against unscrupulous transportation company owners, executives, and senior officials as part of our broader campaign against such exploitative practices," Miller added.

U.S. President Joe Biden's June executive actions aim to limit crossings if they surpass a certain threshold. But it remains unclear how the action is impacting migrants from India, African nations and other countries that account for a growing share of illegal migration.

Biden and U.S. Vice President Kamala Harris, Democrats' presidential candidate in November's contest, have attributed the historic levels of migration to global economic and political instability.

Republican former President Donald Trump, who is seeking another term after losing to Biden in 2020, has blamed the high border crossings on their administration's policies.

(Reporting by Susan Heavey; Editing by Richard Chang)