WASHINGTON — To counter Iran’s arming of Hamas, America will step up its training and arming of the Palestinian Arab president’s personal security services, the American ambassador to Israel said yesterday.

The boost in arms and training is expected to pass easily through Congress this week in a proposed $90 million aid package to elements of the Palestinian Arab polity controlled by the president, Mahmoud Abbas. American counterterrorism officials are already training members of Mr. Abbas’s presidential guard at a facility in Jericho.

The newly trained forces, which could number as many as 3,000, would be deployed at the Rafah border crossing and the Karni crossing, two important Gaza checkpoints through which Israeli officials have said Kassam rockets have been smuggled into the Gaza Strip. But the training would also cover counterterrorism and police functions, according to one senior American diplomat.

Meanwhile, Israeli military officials said this week that dozens or more Hamas gunmen left Gaza recently for training in Iran.

The intended boost to Mr. Abbas comes as the war in Gaza between Hamas, which the State Department has designated as a terrorist organization and which controls the Palestinian Authority ministries, and Mr. Abbas’s party, Fatah, which lost to Hamas in last January’s parliamentary elections, is worsening. Fighting in Gaza has intensified in the last few days after Mr. Abbas, also known as Abu Mazen, called publicly for new elections in a bid to unseat Hamas, which does not recognize Israel.

The Hamas prime minister, Ismail Haniyah, derided America last week after press reports surfaced that America had stepped up training of his rivals.

Yesterday, the American ambassador to Israel, Richard Jones, said: “It’s pretty clear there is one side arming themselves pretty rapidly. That’s not Abu Mazen, that’s not Fatah.” None of the proposed aid and training will go to elements of the Palestinian Authority controlled by Hamas, he added.

The strengthening of Mr. Abbas’s position comes as Secretary of State Rice is planning a trip to the Middle East after President Bush delivers his State of the Union address next month. The aim of the trip is to restart negotiations between Israel and Mr. Abbas. Earlier hopes that a technocratic government could emerge in Gaza and the West Bank have evaporated after earlier negotiations between the two parties broke down in November.

Part of the policy pivot for the Bush administration will be to encourage Israel to bolster Mr. Abbas’s position as well. Yesterday, Jerusalem announced that it would release back tax revenues to portions of Mr. Abbas’s government.

When asked about the pivot yesterday, a State Department spokesman, Sean McCormack, said: “We have talked to them about possibly doing that. We have talked about the possibility of supporting President Abbas in terms of his efforts to exercise some control over the Palestinian areas as in his role as president in terms of supporting the security services and in the confines of his powers providing humanitarian assistance to the Palestinian people.”