Foreign policy experts have warned that lifting economic sanctions on Iran could lead to an increase in terror activities in the region and possibly elsewhere.

While the key point in the debate over Iran's nuclear programme is keeping the Middle East country from developing a nuclear weapon, experts believe that dropping economic sanctions could lead to an increase in terror activities, Fox News said.

The removal of sanctions will "free up extra money to support extremist movements," former US ambassador to Bahrain Adam Ereli said.

"It doesn't take a lot of money – Hezbollah, Hamas, the Houthis in Yemen, they don't need a lot of money... there is plenty to go around," he added.

Tehran has long been linked to the terrorist groups Hezbollah and Hamas. Iran reportedly gave financial and military aid to those two groups in their fight against Israel.

"We should expect some of this money to go toward terrorism ... there is no indication the Iranians will change their ways. In fact, the deal states that Iran does not have to – the relief of sanctions is not contingent upon the Iranians changing their ways," said Hudson Institute adjunct fellow Rebeccah Heinrichs.

Iran is also supporting Houthi rebels in Yemen against the Saudi-backed central government.

According to Ereli, Iran's support to extremist groups was not included in the nuclear deal reached with six world powers as the "scope of the negotiations was defined to include just Iran's nuclear power programme, not its ballistic missile programme, not its support for terror, and, frankly, they wouldn't have come to the table or agreed to negotiate if we had broadened the agenda."

US allies in the Middle East are "worried" that the sanctions relief will allow Iran to increase its military budget and resources.

Some allies in the region have aired concern that Iran will take on a more aggressive foreign policy in the region.

"This [nuclear] deal [with Iran] has basically kicked off what is going to be an arms race in the region because they [US allies in the region] are going to have to arm themselves, at least conventionally against what is going to be a much more militarily superior Iranian regime," said Heinrichs.

"Iran is going to do some things that are contrary to this agreement, undermine the commitments it has made," said Ereli. Looking ahead, "the West will be divided and, because of this agreement, will not be able to make a firm and tough response."

Iran has warned that it "may reconsider its commitments" in the historic nuclear deal if the US, Europe, and UN sanctions cleared under the accord are "impaired by continued application or the imposition of new sanctions with a nature and scope identical or similar to those that were in place prior to the implementation date, irrespective of whether such new sanctions are introduced on nuclear related or other grounds, unless the issues are remedied within a reasonably short time," said Gholamali Khooshroo, Iran's UN envoy, in a statement.