An influential Trump administration official secretly met with a representative of Nicolas Maduro’s regime in Mexico City in September to try to negotiate the Venezuelan leader’s peaceful exit from power.

Ric Grenell, the former Acting U.S. Director of National Intelligence and ambassador to Germany, and Jorge Rodriguez, a Venezuelan politician who is close to Maduro, met in the Mexican capital, according to three people familiar with the matter.

Grenell sought to discuss Maduro’s departure, according to two of the people, but it isn’t clear if Rodriguez and Maduro were open to the possibility. In any event, the talks weren’t successful, the people said.

President Donald Trump has tried to achieve a number of foreign policy accomplishments ahead of the Nov. 3 election, including Mideast peace agreements, troop withdrawals from several countries and the release of U.S. hostages believed to be held in Syria.

U.S. officials gave conflicting accounts on whether Grenell’s trip to meet Rodriguez was authorized ahead of time, although two people familiar with the matter said Trump’s national security adviser, Robert O’Brien, signed off on it with the president’s blessing. The State Department was not informed, one of the people said.

Rodriguez declined to comment, as did spokespeople for the White House National Security Council.

The people familiar with the Venezuela talks asked not to be identified because they were never announced.