It was an awkward day today for the U.S. embassy here.

U.S. diplomat began by presenting one of America's highest military awards to a Thai general charged with embezzling more than $100,000 from the Thai army.

Later, embassy officials were busy explaining circumstances surrounding the discovery of a huge shipment of marijuana bound for California and purportedly sent by an embassy staff member.

Ambassador Charles S. Whitehouse opened the morning by presenting the Legion of Merit to Maj. Gen. Tienchai Sirisumpan in a ceremony in his office. The citation accompanying the medal, signed by former Secretary of Defense Donald himself by assisting U.S. forces during the war in Indochina.

The drug seizure made headlines in afternoon Bangkok newspapers. This and persistent questions by reporters regarding the military award, left embassy officials frazzled.

A statement issued by Whitehouse late in the day said that the embassy had "considered" witholding the Legion of Merit from Tienchai. The ambassador is known to have been annoyed by a report about the impending award that appeared in a Bankok paper earlier this week just a few days after charges were made against Tienchai.

"We read the papers, too, "the ambassador's statement said, "and we saw the allegations of an investigation to be carried out. But, as notice had already been given and ivitations were sent out, we decided to go ahead. This award was earned well before the report of charges was made and we believe that a man is innocent until proven guilty." Two other senior Thai officers receive the award of the same ceremony.

ienchai, commander of the Thai special warfare training center, was charged a week ago by the government Board on Anti-Graft and Corrupt Practices with three counts of misusing more than $100,000 in army funds. The board's secretary general said prima facie evidence had been established.

Tienchai has denied charges, claiming that a complete investigation will show him to be innocent. The government board has turned the case over to the Thai army which has kept him on active duty.

The specific charges against Tienchai are that he failed to report $100,000 income from sale of electricity generated at the special warfare training center; that he failed to report $1,000 earned from a lease of the center's land to another army organization, and that he failed to return half the unspent budget for training programs. The latter amount has not been made public.

Speaking to reporters outside the embassy after the award ceremony, Tienchai said that he had receipts for all the funds.

In citing Tienchai's "exceptionally meritorious service" to U.S. forces between 1966 and 1975, Rumsfeld noted that the officer "continually supported United States-sponsored activities, generously offering the use of personnel, equipment and training facilities . . . His actions have saved the United States millions of dollars and greatly assisted in promoting U.S.-Thai relations.

As Tienchai was leaving the embassy with his new medal, airport customs officials and U.S. Drug Enforcement Agency men were breaking open six crates labeled as the "household effects" of an embassy employee. The crates turned out to contain 1,100 pounds of marijuana.

A DEA source said afterward that the agency was working with Thai authorities to find who had paid $2,600 in cash for the air freight charges and had written a letter that accompanied the shipment requesting that it be dispatched without customs declarations as though it were entitled to diplomatic privilege.

No details about the letter were made public other than that it requested the shipment be treated as he effect of a departing U.S. embassy staff member. Neither the name on the letter nor whether it was on regular embassy stationery was revealed. An embassy official suggested that the letter may have been a forgery, but said he could not yet give any other details.

Thai authorities there are "several suspects," the DEA source said, but we'll wait until the Thais finish their investigation before looking inside the embassy."