Boris Tadić said today that it will demand from the international officials to prevent threats and attempts to deploy Kosovo's customs officials at the administrative line.

"It is particularly worrying for us that those who are ready for such unilateral acts are ready to do so with the use of force," the Serbian president said during a news conference in Belgrade on Tuesday.

He added that "Priština and those who support it" were responsible for the developments in Kosovo.

"Deploying Kosovo customs at administrative crossings does not contribute to peace," he continued.

"I am sending out the message in time that we will not accept such a solution under any kind of pressure," said Tadić.

He added that the fact Serbia was informed about the intentions of the Kosovo Albanian authorities in Priština "does not mean that Serbia is accepting such intentions".

"We will do all we can so that this does not happen, but we must warn international institutions that should it happen, they will be taking over responsibility for any possible consequences," the president warned.

Serbia is counting on all members of the international community who are dedicated to the rule of law, he continued, and added that EU foreign policy chief Catherine Ashton and UN and NATO chiefs "will be contacted with the aim to solve this problem".

"I cannot understand international representatives who are playing with peace and people's lives by making irresponsible decisions - that is supreme irresponsibility and it is dangerous, therefore we will undertake all measures to stop that decision, through all international institutions."

According to him, "the established methodology of experting pressure on Serbia" was very dangerous, and put the government in Belgrade "in a very difficult position".

"There are clear red lines and we will stick to them, but we want compromise solutions, and nobody can accuse us of being the disruptive factor," he noted.

Asked why Serbia accepted the Kosovo customs stamp but not customs workers from Priština, Tadić said it was the UN mission in Kosovo, UNMIK, that "guaranteed the neutrality of the stamp".

According to him, by accepting the stamp that has UNMIK behind it Serbia did not accept Kosovo as independent, nor solutions for the functioning of customs activities on the administrative line.

The president also stressed that the NATO-led troops, KFOR, "cannot be a transport service" for the so-called Albanian customs officers from Priština, but that the peacekeeping mission "must act in the interest of peace and security of all residents of Kosovo and Metohija".

When reporters asked what steps Serbia intends to take if violence once again breaks out in Kosovo, Tadić refused to answer, saying only that he could not "make public every political step" that he plans to take.

Tachi: We are taking over on September 16

Meanwhile Kosovo Prime Minister Hashim Thaci has confirmed that the 16th September Kosovo police and customs officers, with EULEX and KFOR, are going to take over the border crossing Jarinje and Brnjak.

He added that Kosovo's institutions will implement the deal about customs seals in cooperation with the EU and the U.S., and not with Serbia.

"We will implement the agreement with the international factors, and not with Serbia," Thaci said in an interview to Radio "Free Europe" in the Albanian language.

Asked what would happen if Serbia is not ready to implement the agreement, Thaci said that Serbia is "entirely without influence" in this process.

He added that after the agreement with KFOR in early August, the time has come for the implementation of the agreement and establishment of the effective control over the border crossing points at Jarinje and Brnjaka. The income collected at this border crossings for the goods imported from Serbia would go directly to the Kosovo budget, said Tachi.