Ukraine's authorities know who was behind the attempt to poison President Viktor Yushchenko and have traced the substance used in the plot to a laboratory for banned chemical weapons, it emerged yesterday.

　　The former Soviet state's security services had also deployed the same poison to kill others, Mr Yushchenko said in an interview.

　　A number of people suspected of involvement in the assassination attempt last September are on the run, he went on, adding that he was "certain that everybody will be caught" eventually.

　　The disclosure that the poison was made in Ukraine went some way to dispel suspicions that Russia was involved in the plot to get rid of Mr Yushchenko when he was leader of the country's opposition last autumn.

　　However, Petro Poroshenko, the head of Ukraine's security services, refused to rule out the possibility. He said the attempt to kill the president, who fell ill after a dinner with Ukrainian security chiefs, involved "specialists belonging to an existing or former secret service".

　　Mr Yushchenko said a "lot of new information" had recently come to light that would lead to the arrest of the culprits.

　　The president, whose body and bloated face bore the deep scars of the attempt on his life, said he was proud to have overcome the effects of a poison that had killed "a number of others". He refused to be drawn on the circumstances surrounding their deaths.

　　Mr Yushchenko said the remains of the poison were discovered in a Ukrainian laboratory where they were created "in apparent violation of international laws" banning the development of chemical weapons.

　　In fact the assassination attempt only steeled Mr Yushchenko's determination to defy the pro-Moscow regime of Leonid Kuchma - and encouraged the "Orange Revolution" on the streets of Kiev when there was an attempt to fix last winter's elections.

　　Mr Yushchenko, widely seen as a pro-western figure, was eventually elected president in December and rapidly set about building bridges with allies in Europe.

　　Apparently unfazed by the European Union's crisis over its further expansion, Mr Yushchenko said he was convinced that Ukraine would inevitably become part of the "European family''.

　　He said: "Ukraine is a part of Europe and we all have very similar beliefs. Without the Ukraine Europe is incomplete.

　　"I am convinced that during my period in office we will move closer to Europe and that, with the help of others, especially that of Britain, we will become part of Europe not only geographically but politically and economically."