Qatar's Emir Sheikh Tamim bin Hamad Al Thani has issued a decree amending some provisions of a law on "combating terrorism", the state news agency reported.

The decree issued on Thursday included definitions for the terms "terrorist", "crime", "terrorist acts", "terrorist entities", "the freezing of funds" and the "financing of terrorism", according to the Qatar News Agency.

It also identifies procedures related to some "terrorist activities".

The decree stated that individuals and entities accused of "terrorist" activities have the right to challenge charges lodged against them before the court.

Analysis: Qatar-Gulf crisis: Who are the 'terrorists'?

The amendment is effective immediately upon its publication in the government newsletter, the report said.

The order follows an agreement between Qatar and the United States that seeks to curb "terrorism financing," and which was signed during a visit to Doha by US Secretary of State Rex Tillerson.

Qatar was the first state in the Gulf region to sign an agreement with the US on combating "terrorism".

Tillerson had praised Qatar for signing the deal, and for committing to the effort "to track down and disable terror financing".

Saudi Arabia, Bahrain, Egypt and the United Arab Emirates accuse Doha of funding what they call "terrorism" - allegations Qatar strongly denies.

'Baseless accusations'

The four countries cut ties with Qatar on June 5 and imposed a land, air and sea blockade on the country.

On June 22, the Saudi-led group issued a 13-point list of demands, including the shutdown of Al Jazeera, limiting ties with Iran and expelling Turkish troops stationed in the country, as a prerequisite to lifting the blockade.

Doha rejected the demands, and the countries now consider the list null and void.

The blockading countries later issued a six-point demand.

Several Western diplomats have visited the Gulf over the past two weeks in a bid to ease the dispute, yet no breakthrough has been achieved.

Meanwhile, at the United Nations, Qatar's UN ambassador, Alya Ahmed Saif Al Thani, rejected the "baseless accusations" made by Egyptian Deputy UN Ambassador Ihab Awad Moustafa against Doha.

Earlier on Thursday, Moustafa told the UN Security Council that Qatar is adopting a "pro-terrorist" policy that violated UN council resolutions, and said it is "shameful" that the 15-member body had not held Qatar accountable.

Al Thani told Reuters after the meeting: "Egypt is exploiting their Security Council seat to drag in issues that are not relevant to the council's agenda ... it's just serving their own national agenda."

Any push to pass a Security Council resolution against Qatar would likely be difficult as it needs either consensus approval behind closed doors by the council, or a vote on a resolution, which would need nine votes in favour and no vetoes by the US, Britain, France, Russia or China.