White House presses Iraq to block Iranian aid to Syria

 Baghdad must step up its efforts to block Iranian shipments of weapons and aid moving through Iraqi airspace to Syrian forces loyal to embattled President Bashar Assad, the White House said Wednesday. 

"We would like [Iraq] to do more" to rein in or cut off Syrian supply lines running from Tehran, a senior administration official told reporters. 

Specifically, the Obama administration is pressuring Iraqi Prime Minister Nouri al-Maliki to focus on patrolling the air routes used by Iranian forces to smuggle arms and supplies into Syria. 

Iranian supply routes, along with the growing al Qaeda threat in Iraq and Syria, is at the top of the agenda for Maliki's visit to Washington this week. 

The Iraqi delegation met with Vice President Joe BidenJoseph (Joe) Robinette BidenThe Hill's 12:30 Report Pence talks regularly to Biden, Cheney: report Biden moving toward 2020 presidential run: report MORE Wednesday morning, and will meet with congressional leaders later in the day. 

The White House and Congress have repeatedly voiced their concerns over Iraq's ability to block Iranian aid shipments since the beginning of the Syrian civil war three years ago.

"We are greatly disturbed that as the international community works to bring peace to Syria, the Iraqi government is not doing everything in its power to prevent the slaughter of thousands of innocent civilians," Reps. Ted Deutch (D-Fla.) and Tom CottonTom CottonOvernight Finance: GOP criticism of tax bill grows, but few no votes | Highlights from day two of markup | House votes to overturn joint-employer rule | Senate panel approves North Korean banking sanctions GOP senator: CBO moving the goalposts on ObamaCare mandate Cruz: It’s a mistake for House bill to raise taxes MORE (R-Ark.) wrote in a letter to Maliki in March. 

On Tuesday, Sen. John McCainJohn Sidney McCainGOP rushes to cut ties to Moore GOP strategist: 'There needs to be a repudiation' of Roy Moore by Republicans World leaders reach agreement on trade deal without United States: report MORE (R-Ariz.) along with Senate Armed Services Committee chief Carl LevinCarl LevinA lesson on abuse of power by Obama and his Senate allies President Trump, listen to candidate Trump and keep Volcker Rule Republicans can learn from John McCain’s heroism MORE (D-Mich.), ranking member James InhofeJames (Jim) Mountain InhofeMcCain backs Pentagon nominee despite concerns over defense industry ties GOP senators ask Trump for meeting on biofuels mandate Trump feuds endangering tax reform MORE (R-Okla.) rasied the issue again in a letter to President Obama, ahead of Maliki's visit to Washington. 

"We urge you to make clear to Prime Minister Maliki that the extent of Iran’s malign influence in the Iraqi government is a serious problem in our bilateral relationship, especially for the Congress," according to the letter. 

Senate Foreign Relations heads Sens. Robert MenendezRobert (Bob) MenendezIn judge's 2010 Senate trial, Menendez was guilty of hypocrisy Excused Menendez juror: 'I don't think he did anything wrong' We don't need a terrorist attack to know diversity program has to go MORE (D-NJ) and Bob CorkerRobert (Bob) Phillips CorkerTax Foundation: Senate reform bill would cost 6B GOP senators raise concerns over tax plan Dem House candidate apologizes for saying it 'shouldn't take brain cancer' for McCain to show courage MORE (R-Tenn.) also co-signed the letter. 

That said, "policing this is extremely difficult . . . [and] its really an ongoing effort" between Washington and Iraq to shut those supply lines down, the White House official said. 

During the bloodiest days of the Iraq War, U.S. and coalition forces were unable to block similar weapons and supplies shipments from Iran to insurgent groups inside the country. 

For its part, Maliki's government argues it does not have the airpower necessary to ward off the Iranian air shipments. 

To that end, Maliki told reporters in Baghdad he will press the White House to accelerate sales of F-16 warplanes and possible sales of unmanned aircraft to Iraq. 

Washington and Baghdad inked a deal in August to provide Iraq's nascent military with the American jets. 

Without those air assets, Baghdad claims its airspace will remain indefensible to Iranian supplies and support.