On or before December 13, 1898, Gen. Rios declared his intention of leaving Iloilo and transferring to Zamboanga.

In light of this declaration, the foreign and Spanish merchants of Iloilo, none of whom were Americans, wrote a petition to Otis to send American troops to Iloilo, to relieve the Spanish troops, and to occupy Iloilo for their protection.

Otis received this petition on December 13, 1898.

In view of the Iloilo merchants' request for protection, Otis summoned Jose Ner and asked him if the Visayan people are antagonistic towards the Americans. Ner replied that they are not angry with anybody, provided their liberty was not threatened. Otis said he will send a telegram to Washington consulting his government in the matter, and if he is ordered to occupy the Visayan islands he will again summon Sr. Ner.
1205 - Mabini to Aguinaldo, Dec 24 1898

The next day, December 14 1898, Otis cabled Washington regarding the petition, requesting what action he should take, as he can send troops.

Otis cables Mckinley, Dec 14 1898

Otis eagerly awaited a reply as he knew the Spanish troops were hard pressed by Filipinos down south at Iloilo. He thinks that the petition is sufficient ground for intervention, independent of specific instructions from Washington, but Admiral Dewey thinks it unwise as authority is already being sought. Furthermore, both of them think that General Rios would hold out. (Otis is asking Dewey that one of his warships convoy the troops.)
Otis Awaits Reply to His Dec 14 1898 Cable

However, Mckinley was away from Washington. He's on a southern trip to Atlanta and Macon, Georgia, and would not come back until December 21, 1898.

No response was received until December 19, 1898.
Otis Awaits Reply to His Dec 14 1898 Cable

On December 19, 1898, Otis was informed that the President and Secretary were absent from Washington, and that a consideration of his question would await their return, which would be shortly.

Corbin to Otis, Dec 18 1898

On December 23, 1898, Otis finally received a cable from Washington to go ahead and send troops to Iloilo.

Corbin to Otis, Dec 21 1898

Otis conveyed Mckinley's order to Admiral Dewey.

Afterwards, Otis cabled Rios in Iloilo, to inform him of the American troops soon to arrive. He sent the cable to Capiz as the continuing line from Capiz to Iloilo was disrupted, and boats would pick up the messages at Capiz and bring them to Iloilo.

Otis cables Rios, Dec 23 1898

Otis summoned Ner again, and three others (Francisco Soriano, Nicolas Jalandoni, Claudio Lopez, and Jose Ner). He showed them Mckinley's order for him to send troops to Iloilo. The general requested them to intercede with the Visayan revolutionists in order to avoid any shedding of blood. He had reserved four state-rooms for them on USS Newport that is to leave soon together with the Iloilo Expedition. Otis awaited for their reply until 2 o'clock p.m. the next day.
1205 - Mabini to Aguinaldo, Dec 24 1898
1207 - Buencamino, Dec 25 1898

After the meeting with Otis, Ner requested Mabini's opinion, whether he (Ner) should go or not go with the Americans, and whether he should be or not be a mediator. As Aguinaldo was out of town and cannot be consulted, Mabini summoned the council of government. Present at the meeting were Sr. Trias, Alas, and Canon, the other secretaries being absent.
1205 - Mabini to Aguinaldo, Dec 24 1898

The next morning, December 24, 1898, the superintendent of the cable company informed Otis that his cable to Rios yesterday arrived late and wasn't picked up at Capiz. Two gunboats left Capiz at 5:35 p.m. with collected telegrams for Iloilo, but Otis' cable arrived in Capiz 15 minutes later, at 5:50 p.m., so it wasn't included.

Also, the cable operator reported that General Rios would leave Iloilo with all Spaniards that afternoon (on the afternoon of December 24, 1898.)

Otis immediately arranged an alternative way to reach Rios, hopefully before he can leave Iloilo.

Lt. Col. Potter left Manila that night for Iloilo by boat, with a request for Rios that they continue to hold Iloilo until the American troops could arrive.

Unbeknownst to Otis, that same day (December 24, 1898), Rios was also sending a cable to him, that he would go to Manila at the end of the month. Otis would receive it three days later on December 27, 1898.

Rios cables Otis, December 24, 1898

After giving instructions to Lt. Col. Potter, Otis proceeded to create the Iloilo Expedition.

Otis issued the first two of his three orders relating to the Iloilo Expedition.

First, Otis issued General Order No. 39. creating the Expedition.

Otis Creates Miller Iloilo Expedition

Secondly, Otis provided the initial special instructions to Miller.

Otis Initial Instructions to Miller

On December 26, 1898, Otis cabled Washington that the Iloilo Expedition will be leaving that evening.

Otis cables Washington, December 26, 1898

Otis then issued the last of his three orders relating to the Iloilo Expedition.

He provided Miller his further instructions on what to do in Iloilo.

Otis Further Instructions to Miller

The Iloilo Expedition left Manila near midnight of December 26, 1898.

It was composed of five ships, bearing the following units:
1. USAT Newport - Light Battery G, 6th U.S. Artillery,
2. USAT Arizona - 18th U.S. Infantry,
3. USAT Pennsylvania - 51st Iowa Volunteer Infantry,
4. S.S. Union - Filipinos native to Panay Island, formerly with the Spanish Army
5. USS Baltimore (Naval Escort)
General Miller's Arrival at Iloilo

On the steamship S.S. Union were Filipinos native to Panay Island, formerly with the Spanish Army, that Miller intended to land in Iloilo as a goodwill gesture.
S.S. Union

The next day, December 27 1898, Otis cabled Washington about the Iloilo Expedition's departure last night, and that it should arrive tomorrow in Iloilo.

Otis cables Washington Dec 27 1898