International Desk: Mexico has deployed 6,000 members of its National Guard on its border with Guatemala in an attempt to stem the flow of migrants heading to the US.
Mexico's Foreign Minister Marcelo Ebrard is in Washington trying to stop the US from placing trade tariffs on Mexican goods over illegal migration.
US President Donald Trump has vowed to enact import duties of 5% on Monday if no agreement is reached.
On Wednesday, he said "not nearly enough" progress was being made.
After the latest talks on Thursday, Mr Ebrard said he was "an optimistic man."
He said forces would be stationed on Mexico's southern border with Guatemala to prevent migrants entering the country.
"We have explained that there are 6,000 men and that they will be deployed there," he said, adding that talks would continue Friday.
Under the US president's proposal, duties would rise by 5% every month on goods including cars, beer, tequila, fruit and vegetables, reaching 25% by October.
Mr Trump wants Mexico to stop the hundreds of thousands of mostly Central American migrants who have been seeking entry to the US this year.
The president announced the planned Mexico tariffs last week on Twitter, catching members of his own party and financial markets unawares.
US Customs and Border Protection announced this week that migrant arrests had surged in May to the highest level in more than a decade.
Border Patrol apprehended 132,887 migrants attempting to enter the US from Mexico in May, marking a 33% increase from the month before.
It said 84,542 were families and 11,507 unaccompanied children.
The arrests were the highest monthly total since Mr Trump took office.
risingbd/Dhaka/Jun 7, 2019/Nasim