Tensions between Iran and the West escalated after Tehran seized British naval personnel and Iranian President Mahmoud Ahmadinejad cancelled a planned trip to UN Security Council which is to vote on a new resolution against Iran's nuclear program on Saturday.

The British Ministry of Defense (MoD) said on Friday that 15 British naval personnel were seized by Iranian forces at a bordering river between Iran and Iraq, demanding Iran immediately free the soldiers and equipment.

The incident took place at approximately 10:30 Iraqi time (0730 GMT) when the British soldiers were engaged in routine boarding operations of merchant shipping in Iraqi territorial waters, the MoD said in a statement.

"The UK boarding party had completed a successful inspection of a merchant ship when they and their two boats were surrounded and escorted by Iranian vessels into Iranian territorial waters," said the MoD.

"We are urgently pursuing this matter with the Iranian authorities at the highest level," it said, adding that "on the instructions of the foreign secretary, the Iranian ambassador has been summoned to the Foreign Office."

Iranian Foreign Ministry later confirmed the incident, but it denied the British allegation and accused the British soldiers of entering Iranian territorial waters illegally.

"This is not the first time for British military personnel to enter the Iranian waters illegally since they occupied Iraq," Ibrahim Rahimpour, director general for Western European Affairs of the Foreign Ministry was quoted as saying.

Rahimpour added that Tehran had summoned the top British envoy and demanded the London administration explain the illegal entry of British sailors into Iranian territorial waters.

"We have summoned British charge d'affaires Kate Smith to the foreign ministry to receive the firm protest for the illegal entry of British sailors into Iranian territorial waters," he said, urging the British government to ensure "not to do this again" in the future.

The detaining incident came before the UN Security Council is due to vote on a new resolution against Iran's nuclear program on Saturday, raising expectation that it may increase the determination of the West to push forward new punitive sanctions.

Meanwhile, Iranian President Mahmoud Ahmadinejad cancelled a planned trip to the UN Security Council, accusing the U.S. of delaying the visa issuance.

Ahmadinejad cannot speak before the council due to the "U.S. obstacle on visa issuance" to him and his delegation, Foreign Ministry spokesman Mohammed Ali Hosseini was quoted as saying by the state television on Friday night.

Instead, Foreign Minister Manouchehr Mottaki will go to New York to attend the meeting and "explain Iran's position on the nuclear issue," Hosseini said.

"The Americans have triumphantly prevented President Ahmadinejad from joining the conference through their failure to issue visas for him and his accompanying delegation," he added.

According to some Western reports, Mohammad Mir Ali Mohammadi, press secretary of Iran's mission at the UN, said the U.S. government had not granted the needed visas to U.S. Embassy in Switzerland in time for the Iranian president to visit New York.

Besides, Iran's Deputy Foreign Minister for International and Legal Affairs Abbas Araghchi also accused the U.S. officials of following their unilateral approaches by visa refusal for the Iranian president.

"It is blatant violation of the consular undertaking of the UN host country in dealing with visa requests for officials of the United Nations member states and another indication of the U.S. ill-intention toward Iranian nuclear program," he stressed.

But, the U.S. State Department said tit for tat on Friday that the White House had already delivered visas for the Iranian president and his 38 corteges so he could express his opinions at the meeting when the Security Council member states begin to vote on the resolution.

The five permanent member states of the Security Council -- the United States, Russia, China, Britain and France -- plus Germany are seeking to impose more severe sanctions on Iran after it failed to respect Resolution 1701 which calls for Tehran's suspension of uranium enrichment.

The Islamic Republic insists its nuclear program is for civilian purposes only.

Source: Xinhua