WASHINGTON, DC (CNSNews.com) -  Contending that the "Arab spring" has made non-Muslim religious minorities in the Middle East more vulnerable than ever, Rep. Frank Wolf (R-Va.) is voicing frustration over the State Department holding up a Senate bill to appoint a special envoy focusing on the issue.

"I am concerned that time is running out - both in terms of the legislative calendar for this year and in terms of the plight of these communities," he wrote in a letter to Secretary of State Hillary Clinton late last week. "[D]espite the strategic imperative and the moral obligation to act, the State Department seems unable or unwilling to address the issue with the urgency it demands," he wrote.

Wolf, who introduced a House bill creating the envoy post - it passed last year with strong bipartisan support - attributes the block  to Sen. Jim Webb (D-Va.) and says Senate Foreign Relations Committee chairman John Kerry (D-Mass.) also has disregarded his requests for a hearing on the matter.

Webb's spokesman declined to comment, but last July he told CNSNews.com the State Department had advised the senator that the appointment of a special envoy would be "unnecessary, duplicative, and likely counterproductive."

In his letter to Clinton, Wolf wrote that Webb also had indicated he was uncomfortable about the legislation moving ahead without being subject to a Senate Foreign Relations Committee hearing. Wolf had written to Kerry on July 23 requesting such a hearing, to no avail.

Kerry's office did not respond to request for comment.

Wolf's bill, H.R. 440, establishes a special envoy to promote religious freedom specifically in the Middle East and South-Central Asia. Co-sponsored by 80 lawmakers from both parties, it passed in the House in July 2011 by a 420-20 vote.

It has languished in the Senate ever since, along with a companion bill, S. 1245, introduced in June 2011 by Sens. Roy Blunt (R-Mo.) and Carl Levin (D-Mich.) and co-sponsored by two Republicans and three Democrats.

"Despite the introduction of the bill having pre-dated the so-called 'Arab Spring,' the dramatic changes in the region over the last year have only made these communities more vulnerable," Wolf wrote to Clinton. "As such, a special envoy has never been more needed."

Wolf pointed to troubling times facing Copts in Egypt, the exodus of Christians from Iraq and the assassination of Pakistan's only Christian cabinet member over his support for a Christian woman sentenced to death on blasphemy charges.

"I am disappointed in Senator Webb for having put a hold on this bill and preventing it from moving, despite the obvious need for renewed attention to this issue and the very fact that not one Democrat voted against the House-passed bill. I am particularly disheartened by Chairman Kerry's lack of action - despite my repeated requests for a vote or hearing."

In its advice to Webb earlier this year, the State Department said the legislation infringes on the secretary of state's "flexibility to make appropriate staffing decisions." It stated that diplomats from Clinton down consistently raise religious freedom concerns, both in meetings in the U.S. and while traveling abroad.

H.R. 440, the Near East and South Central Asia Religious Freedom Act, created an envoy to promote religious freedom for minorities in 31 specified countries stretching from Morocco to Bangladesh.

It gave priority to four countries that are considered by religious freedom advocates to be among the most dangerous places to be a Christian or other religious minority - Pakistan, Egypt, Iran and Afghanistan.

The legislation provides for the envoy, appointed by the president and reporting to the president and secretary of state, to work with foreign governments to address discriminatory laws, and to recommend to the U.S. government appropriate responses to violations.

At the time of its passage a Muslim Brotherhood leader in Egypt warned it would bring more U.S. "interference" in Egypt's affairs. Christian activists in Pakistan welcomed the move.

The 31 countries identified in the legislation are:

Middle East: Algeria, Bahrain, Egypt, Iran, Iraq, Israel, Jordan, Kuwait, Lebanon, Libya, Morocco, Oman, Qatar, Saudi Arabia, Syria, Tunisia, United Arab Emirates, Yemen, plus the West Bank and Gaza.