Crude oil futures fell on Tuesday as optimism faded for an output-limiting deal from an oil producer meeting in Algeria that has so far failed to yield any agreement to curb one of the worst supply gluts in history, Reuters reports.

Saudi Arabia on Tuesday dashed hopes that OPEC oil producers could clinch a deal in Algeria this week after sources within the exporter group said differences between the kingdom and rival Iran remained too wide.

Brent crude futures slipped 85 cents to $46.50 a barrel by 1113 GMT, having closed up $1.46, or 3.2 percent, in the previous session.

U.S. West Texas Intermediate (WTI) crude fell 79 cents to $45.14 a barrel, after rising $1.45, or 3.3 percent, in the previous session.

“It’s all about what’s going on in Algiers really … the prospect or no prospect of a supply deal,” Olivier Jakob, oil analyst at Petromatrix, said. “There is no new fundamental development that is more important than Algiers.”

Sources told Reuters last week that Saudi Arabia had offered to reduce its output if Iran agreed to freeze production. But Iran played down the chances of a deal, saying the meetings in Algiers were only advisory.

Russia’s oil minister on Tuesday also said that the country would want to freeze oil output at current levels; Russia’s oil output recently touched an all-time high of 11.75 million barrels per day (bpd).