WASHINGTON - The United States and Europe will slap new sanctions against Russia this week in the wake of its continued assistance to rebels in eastern Ukraine, US media reported Monday.

"We expect the European Union to take significant steps" this week to target Russia's economy, news website The Hill quoted Tony Blinken, US President Barack Obama's deputy national security adviser, as saying.

Blinken said the United States will also impose additional costs itself, according to The Hill.

On Monday, Obama spoke about these next steps in a video conference call with British Prime Minister David Cameron, French President Francois Hollande, German Chancellor Angela Merkel and Italian Prime Minister Matteo Renzi, Blinken said.

"Russia is headed for economic contraction, not growth, which is a reversal" because of existing Western sanctions, said Blinken, who did not elaborate on the details of the forthcoming sanctions.

Over the conference call on Monday, the world leaders stressed the continued need for unrestricted access to the shoot-down site of Malaysia Airlines Flight 17 to allow for recovery of victims' remains and for international investigators to proceed with their efforts, the White House said in a statement.

The US and European leaders also discussed situations in Gaza, Iraq and Libya, said the statement.

On the situation in Gaza, the leaders agreed on the need for an immediate, unconditional humanitarian ceasefire, noting shared concern about the risk of further escalation and the loss of more innocent lives.

Israel launched a large-scale operation on July 8 on the Gaza Strip, which has so far left 1,030 Palestinians and 43 Israelis killed and more than 6,000 Palestinians injured.

The leaders also discussed the security challenges in Iraq, welcoming developments in the political process, and urging the swift completion of the formation of an inclusive government, the statement said.

With respect to Libya, they agreed on the need for an immediate ceasefire among militias in Tripoli, called for the seating of the newly elected Council of Representatives, and underscored support for the UN in seeking a resolution to this conflict, it added.

Libya has seen a drastic escalation of violence since the 2011 turmoil which toppled its former leader Muammar Gaddafi. The recent battle between Islamist fighters and pro-secular militias around Tripoli's international airport has killed at least 97 and wounded 404, paralyzing most of the air traffic in the north African country.