United States President Donald Trump has warned that he would endorse attacks on Hamas, effectively breaking the ceasefire between Israel and the Palestinian group, if it continues to target gangs and alleged Israeli collaborators in Gaza.

“If Hamas continues to kill people in Gaza, which was not the Deal, we will have no choice but to go in and kill them,” Trump wrote in a social media post on Thursday. “Thank you for your attention to this matter!”

In an interaction with reporters later, Trump qualified that threat to make clear that US forces would not be entering Gaza.

“It’s not going to be us,” Trump said. “We won’t have to.”

“There are people very close, very nearby that will go in and they’ll do the trick very easily, but under our auspices,” the US president said, in an apparent reference to Israel, without naming the country.

The threats against Hamas appear to signal an about-face from Trump, who earlier this week suggested that he was fine with the group’s crackdown on gangs in the Palestinian territory.

“They did take out a couple of gangs that were very bad, very, very bad gangs,” Trump told reporters on Tuesday. “And they did take them out, and they killed a number of gang members. And that didn’t bother me much, to be honest with you. That’s OK.”

There have been deadly clashes reported between Hamas and armed clan members in Gaza, who have been accused of looting humanitarian aid and working for Israel.

After the fighting on Sunday, the Interior Ministry in Gaza issued a general amnesty for gang members who did not participate in the bloodshed.

In June, Israeli officials admitted to arming Gaza gangs, some of which have ties to ISIL (ISIS), in an effort to destabilise Hamas.

On Sunday, gunmen from a Gaza gang linked to Israel killed prominent Palestinian journalist Saleh Aljafarawi, according to local forces.

Earlier this week, Palestinian Authority President Mahmoud Abbas condemned Hamas over accusations that the group executed suspected Israeli collaborators, calling the purported killings a “heinous crime”.

“What happened represents a crime, a flagrant violation of human rights, and a serious assault on the principle of the rule of law,” Abbas’s office said in a statement.

But the Gaza gangs aren’t the only issue on which Trump has threatened Hamas.

Under the US president’s ceasefire plan, Hamas is expected to disarm and end any role in the governance of Gaza. But it is not clear whether the group has agreed to these conditions.

On Thursday, Trump warned that if Hamas did not disarm on its own, it would be forced to do so.

“They will disarm, and if they don’t do so, we will disarm them, and it’ll happen quickly and perhaps violently,” Trump told reporters.

The truce has largely held since coming into effect on Saturday. But Israel has repeatedly violated the agreement, killing Palestinians daily under the justification that they approached areas under the control of the Israeli military, which are not clearly marked.

Israel has also threatened to once again restrict humanitarian aid to Gaza, accusing Hamas of failing to return all the bodies of the captives it held. And it has delayed the opening of the Rafah crossing between the Palestinian enclave and Egypt, to facilitate movement in and out of the territory.

Trump has hailed the ceasefire