President Obama called Wednesday for a "new conceptual framework" to replace Israel's blockade of the Gaza Strip, saying he thinks the effort should be narrowed to focus only on arms shipments.

Obama said a new blockade could target the weapons that Israel says are being used against its citizens, "rather than focusing in a blanket way on stopping everything and then, in a piecemeal way, allowing things into Gaza."

The comments, made Wednesday after a White House meeting with Palestinian Authority President Mahmoud Abbas, reflect the administration's willingness to pressure Israel since commandos stormed an aid flotilla headed for Gaza on May 31, killing nine people. The commandos had come under attack by passengers wielding pipes.

Obama's remarks reinforced the message sent by Secretary of State Hillary Rodham Clinton last week, in which she indicated the United States believes Israel must relent in its efforts to cut off all shipments to Gaza. "The situation in Gaza is unsustainable and unacceptable," Clinton had said in a statement after the incident.

The White House announced Wednesday that it was increasing aid to Gaza by $400 million, saying it would help provide access to clean drinking water, build schools and expand health-care facilities. It was unclear, however, how materials to achieve those goals would get to Gaza.

Abbas has no authority in Gaza, which is overseen by Hamas, an Islamist organization that refuses to recognize Israel's right to exist and does not recognize agreements between Israel and Abbas's Palestinian Authority. The United States considers Hamas a terrorist group.

Israel's blockade of Gaza is aimed both at preventing weapons from entering the narrow coastal strip and weakening Hamas with crippling economic restrictions. Few construction materials have been allowed into the territory, and everyday items such as coriander have also been prohibited in recent years.

In his remarks after meeting with Abbas, Obama said that both men recognize Israel's security needs. But he made clear that humanitarian needs in Gaza are being hampered by the blockade.

"And so there should be a means by which we are able to stop the flow of arms that could endanger Israel's security at the same time we're doing so in a way that allows the people in Gaza to live out their aspirations and their dreams, both for themselves and their children," Obama said.

The two men also talked about the broader effort to bring peace to the region by moving once again toward direct talks between the Palestinians and Israelis. Abbas said that could happen once there is progress in indirect talks, which are underway.

"With regards to the transitioning from the proximity talks to the direct talks . . . we are not saying that we have conditions," Abbas said. "What has happened is that we agreed that, should a progress be achieved, then we would move on to direct talks."

Obama had been planning to raise the subject of direct talks with Israeli Prime Minister Binyamin Netanyahu during a White House meeting last week. But that meeting was canceled when Netanyahu rushed home following the flotilla incident.

"In the long run, the only real way to solve this problem is to make sure that we've got a Palestinian state side-by-side with an Israel that is secure," Obama said.