Thaksin began his tour of the provinces on Saturday, after a week of registrations for election candidates began last Thursday. He had met thousands of supporters in the North and Northeast, but yesterday was the first time he had encountered protesters outside of Bangkok.

Local authorities at the Aranyaprathet border checkpoint in Sa Kaew narrowly managed to prevent a clash between the protesters and about 500 Thaksin supporters, as both sides exchanged heated arguments.

Some of the protesters held placards with messages like, "Why are you here, man of no ethics?" and, "Thaksin, get out". Some of the messages also praised Snoh as the "creator" of the ruling Thai Rak Thai Party.

Before Thaksin arrived, local authorities ordered the removal of a stage set up by the protesters.

Just a few hundred metres away from the protesters, Thaksin supporters gathered and gave him flowers.

While the prime minister was listening to a report from local officials about border trade near the customs office, the protesters moved closer and shouted repeatedly, "Thaksin, get out". About 50 soldiers formed a barrier to prevent them from advancing further.

Earlier in the day, the premier and his entourage, which included his son Panthongtae, were in Nakhon Nayok to visit a weekly market set up under the government's policy of promoting local products.

About 2,000 local residents gathered there to welcome Thaksin. He told them that thanks to his government's policies, such as the electric-train links with the capital, Nakhon Nayok was growing rapidly to become part of the Bangkok metropolis. "Nakhon Nayok has seen tremendous changes over the past few years," he said.

He apologised to his supporters for failing to greet all of them due to his tight schedules.

Thaksin said he left home late in the morning because, "I have so many things to deal with these days. Many people give me headaches and my time has been wasted on this nonsense."

The premier will join the ruling party's election rally today in Chon Buri, according to Sanga Thanasanguanwong, one of Thai Rak Thai's candidates in the eastern province.

Thaksin and a number of the party's key men, including Adisorn Piengket, Chaturon Chaisang and Sora-at Klinpratoom will address the rally outside the Provincial Hall, which is scheduled to start at 6pm, Sanga said. He said he expected about 10,000 people to attend.

In a related development, Thai Rak Thai deputy leader Sudarat Keyuraphan yesterday denied there were any political implications in a meeting between Thaksin and Chat Thai Party secretary-general Prapat Pothasuthon on Tuesday evening. She said that the premier had simply had dinner with his long-time friend Prapat at the latter's house in Suphan Buri.

Chat Thai has joined the Democrat and Mahachon parties in boycotting the April 2 general elections.

Prapat yesterday said it would have been impolite of him to reject Thaksin's request to have dinner with him. "If this is viewed as improper, I'm ready to explain myself," he said.