WASHINGTON — The Obama administration has decided not to sign an international convention banning land mines.

State Department spokesman Ian Kelly said Tuesday that the administration recently completed a review and decided not to change the Bush-era policy.

“We decided that our land mine policy remains in effect,” he said.

More than 150 countries have agreed to the Mine Ban Treaty’s provisions to end the production, use, stockpiling and trade in mines. Besides the United States, holdouts include: China, India, Pakistan, Myanmar and Russia.

Sen. Patrick Leahy, D-Vt., criticized the State Department’s review of the land mine policy as “cursory and halfhearted.”

The senator described the decision to stand fast on the current policy as “a lost opportunity .... The United States took some of the earliest and most effective steps to restrict the use of land mines. We should be leading this effort, not sitting on the sidelines.”

Human rights groups had expressed hopes that the Obama administration would sign the treaty.

Stephen Goose, the director of Human Rights Watch’s arms division, said he was surprised by the announcement and called it disappointing. He said that his group had been pushing the administration to conduct a review of its policy but that the administration had given no indication that one was under way.

“If one was already completed, it was not very extensive,” he said.

Kelly said that the United States would send an observer group of mine experts to a review conference on the treaty in Cartegena, Colombia, next week.

A report this month by the International Campaign to Ban Landmines found that mines remain planted in the earth in more than 70 countries and killed at least 1,266 people and wounded 3,891 last year. More than 2.2 million anti-personnel mines, 250,000 anti-vehicle mines and 17 million other explosives left over from wars have been removed since 1999, the report said.