GOP Sen. John Cornyn (Texas) became the latest member of his party to question part of the United States's military involvement in Libya.

The senator tweeted Sunday night, questioning whether Congress would ever sign off on President Obama's actions:

On Libya, is Congress going to assert it's constitutional role or be a potted plant?

Cornyn appeared to echo House Speaker John Boehner (R-Ohio), who on Sunday pressured Obama to better explain the U.S.'s objectives in Libya, where forces loyal to the country's leader, Col. Moammar Gadhafi, have violently clashed with rebels for weeks.

Under the War Powers Act, the president must inform Congress of any military resolution within 48 hours and limit military action to 60 days without further congressional approval.

Should Congress act on the Libya conflict, it likely won't do so this week: Lawmakers are on a week-long recess.

President Obama and many members of Congress have said the goal for U.S. intervention in Libya is regime change. Appearing on Sunday talk shows, however, Adm. Mike Mullen said the U.S. mission is to first protect Libyan civilians from the forces of leader Col. Moammar Gadhafi and keep supply lines open for humanitarian aid.

Other Republicans have been critical of the way the mission has been carried out. Sens. John McCain (Ariz.) and Lindsey Graham (S.C.) dinged Obama on the Sunday talk shows for not acting quickly or broadly enough.

Sen. Richard Lugar (R-Ind.), however, warned that the U.S. intervention could last a long time and questioned why America has not taken similar action in Yemen and Bahrain, where popular uprisings are being suppressed.